res_pjsip_registrar.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2013, 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_pjproject</depend>
    <depend>res_pjsip</depend>
    <support_level>core</support_level>
 ***/
 
#include "asterisk.h"
 
#include <signal.h>
#include <pjsip.h>
#include <pjsip_ua.h>
 
#include "asterisk/res_pjsip.h"
#include "asterisk/module.h"
#include "asterisk/paths.h"
#include "asterisk/test.h"
#include "asterisk/taskprocessor.h"
#include "asterisk/manager.h"
#include "asterisk/named_locks.h"
#include "asterisk/res_pjproject.h"
#include "res_pjsip/include/res_pjsip_private.h"
 
/*** DOCUMENTATION
    <manager name="PJSIPShowRegistrationsInbound" language="en_US">
        <synopsis>
            Lists PJSIP inbound registrations.
        </synopsis>
        <syntax />
        <description>
            <para>
            In response, <literal>InboundRegistrationDetail</literal> events showing configuration
            and status information are raised for all contacts, static or dynamic.  Once all events
            are completed an <literal>InboundRegistrationDetailComplete</literal> is issued.
            </para>
            <warning><para>
                This command just dumps all coonfigured AORs with contacts, even if the contact
                is a permanent one.  To really get just inbound registrations, use
                <literal>PJSIPShowRegistrationInboundContactStatuses</literal>.
            </para>
            </warning>
        </description>
        <see-also>
            <ref type="manager" module="res_pjsip_registrar">PJSIPShowRegistrationInboundContactStatuses</ref>
        </see-also>
    </manager>
    <manager name="PJSIPShowRegistrationInboundContactStatuses" language="en_US">
        <synopsis>
            Lists ContactStatuses for PJSIP inbound registrations.
        </synopsis>
        <syntax />
        <description>
            <para>
            In response, <literal>ContactStatusDetail</literal> events showing status information
            are raised for each inbound registration (dynamic contact) object.  Once all events
            are completed a <literal>ContactStatusDetailComplete</literal> event is issued.
            </para>
        </description>
    </manager>
 ***/
 
static int pj_max_hostname = PJ_MAX_HOSTNAME;
static int pjsip_max_url_size = PJSIP_MAX_URL_SIZE;
 
/*! \brief Internal function which returns the expiration time for a contact */
static unsigned int registrar_get_expiration(const struct ast_sip_aor *aor, const pjsip_contact_hdr *contact, const pjsip_rx_data *rdata)
{
    pjsip_expires_hdr *expires;
    unsigned int expiration = aor->default_expiration;
 
    if (contact && contact->expires != PJSIP_EXPIRES_NOT_SPECIFIED) {
        /* Expiration was provided with the contact itself */
        expiration = contact->expires;
    } else if ((expires = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_EXPIRES, NULL))) {
        /* Expiration was provided using the Expires header */
        expiration = expires->ivalue;
    }
 
    /* If the value has explicitly been set to 0, do not enforce */
    if (!expiration) {
        return expiration;
    }
 
    /* Enforce the range that we will allow for expiration */
    if (expiration < aor->minimum_expiration) {
        expiration = aor->minimum_expiration;
    } else if (expiration > aor->maximum_expiration) {
        expiration = aor->maximum_expiration;
    }
 
    return expiration;
}
 
/*! \brief Structure used for finding contact */
struct registrar_contact_details {
    /*! \brief Pool used for parsing URI */
    pj_pool_t *pool;
    /*! \brief URI being looked for */
    pjsip_sip_uri *uri;
};
 
/*! \brief Callback function for finding a contact */
static int registrar_find_contact(void *obj, void *arg, int flags)
{
    struct ast_sip_contact *contact = obj;
    const struct registrar_contact_details *details = arg;
    pjsip_uri *contact_uri;
 
    if (ast_tvzero(contact->expiration_time)) {
        return 0;
    }
 
    contact_uri = pjsip_parse_uri(details->pool, (char*)contact->uri, strlen(contact->uri), 0);
    if (!contact_uri) {
        ast_log(LOG_WARNING, "Unable to parse contact URI from '%s'.\n", contact->uri);
        return 0;
    }
 
    return (pjsip_uri_cmp(PJSIP_URI_IN_CONTACT_HDR, details->uri, contact_uri) == PJ_SUCCESS) ? CMP_MATCH : 0;
}
 
/*! \brief Internal function which validates provided Contact headers to confirm that they are acceptable, and returns number of contacts */
static int registrar_validate_contacts(const pjsip_rx_data *rdata, pj_pool_t *pool, struct ao2_container *contacts,
    struct ast_sip_aor *aor, int permanent, int *added, int *updated, int *deleted)
{
    pjsip_contact_hdr *previous = NULL;
    pjsip_contact_hdr *contact = (pjsip_contact_hdr *)&rdata->msg_info.msg->hdr;
    struct registrar_contact_details details = {
        .pool = pool,
    };
 
    for (; (contact = (pjsip_contact_hdr *) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, contact->next)); pj_pool_reset(pool)) {
        unsigned int expiration = registrar_get_expiration(aor, contact, rdata);
        struct ast_sip_contact *existing;
        char contact_uri[pjsip_max_url_size];
 
        if (contact->star) {
            /* The expiration MUST be 0 when a '*' contact is used and there must be no other contact */
            if (expiration != 0 || previous) {
                return -1;
            }
            /* Count all contacts to delete */
            *deleted = ao2_container_count(contacts) - permanent;
            previous = contact;
            continue;
        } else if (previous && previous->star) {
            /* If there is a previous contact and it is a '*' this is a deal breaker */
            return -1;
        }
        previous = contact;
 
        if (!PJSIP_URI_SCHEME_IS_SIP(contact->uri) && !PJSIP_URI_SCHEME_IS_SIPS(contact->uri)) {
            continue;
        }
 
        details.uri = pjsip_uri_get_uri(contact->uri);
 
        /* pjsip_uri_print returns -1 if there's not enough room in the buffer */
        if (pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, details.uri, contact_uri, sizeof(contact_uri)) < 0) {
            /* If the total length of the uri is greater than pjproject can handle, go no further */
            return -1;
        }
 
        if (details.uri->host.slen >= pj_max_hostname) {
            /* If the length of the hostname is greater than pjproject can handle, go no further */
            return -1;
        }
 
        /* Determine if this is an add, update, or delete for policy enforcement purposes */
        existing = ao2_callback(contacts, 0, registrar_find_contact, &details);
        ao2_cleanup(existing);
        if (!existing) {
            if (expiration) {
                ++*added;
            }
        } else if (expiration) {
            ++*updated;
        } else {
            ++*deleted;
        }
    }
 
    return 0;
}
 
enum contact_delete_type {
    CONTACT_DELETE_ERROR,
    CONTACT_DELETE_EXISTING,
    CONTACT_DELETE_UNAVAILABLE,
    CONTACT_DELETE_EXPIRE,
    CONTACT_DELETE_REQUEST,
    CONTACT_DELETE_SHUTDOWN,
};
 
static int registrar_contact_delete(enum contact_delete_type type, pjsip_transport *transport,
    struct ast_sip_contact *contact, const char *aor_name);
 
/*! \brief Internal function used to delete a contact from an AOR */
static int registrar_delete_contact(void *obj, void *arg, int flags)
{
    return registrar_contact_delete(
        CONTACT_DELETE_REQUEST, NULL, obj, arg) ? 0 : CMP_MATCH;
}
 
/*! \brief Internal function which adds a contact to a response */
static int registrar_add_contact(void *obj, void *arg, int flags)
{
    struct ast_sip_contact *contact = obj;
    pjsip_tx_data *tdata = arg;
    pj_str_t uri;
    pjsip_uri *parsed;
 
    pj_strdup2_with_null(tdata->pool, &uri, contact->uri);
    parsed = pjsip_parse_uri(tdata->pool, uri.ptr, uri.slen, PJSIP_PARSE_URI_AS_NAMEADDR);
 
    if (parsed && (PJSIP_URI_SCHEME_IS_SIP(parsed) || PJSIP_URI_SCHEME_IS_SIPS(parsed))) {
        pjsip_contact_hdr *hdr = pjsip_contact_hdr_create(tdata->pool);
        hdr->uri = parsed;
        if (!ast_tvzero(contact->expiration_time)) {
            hdr->expires = ast_tvdiff_ms(contact->expiration_time, ast_tvnow()) / 1000;
        } else {
            hdr->expires = PJSIP_EXPIRES_NOT_SPECIFIED;
        }
        pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr *) hdr);
    } else {
        ast_log(LOG_WARNING, "Skipping invalid Contact URI \"%.*s\" for AOR %s\n",
            (int) uri.slen, uri.ptr, contact->aor);
    }
 
    return 0;
}
 
static const pj_str_t path_hdr_name = { "Path", 4 };
 
static int build_path_data(pjsip_rx_data *rdata, struct ast_str **path_str)
{
    pjsip_generic_string_hdr *path_hdr = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &path_hdr_name, NULL);
 
    if (!path_hdr) {
        return 0;
    }
 
    *path_str = ast_str_create(64);
    if (!*path_str) {
        return -1;
    }
 
    ast_str_set(path_str, 0, "%.*s", (int)path_hdr->hvalue.slen, path_hdr->hvalue.ptr);
 
    while ((path_hdr = (pjsip_generic_string_hdr *) pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &path_hdr_name, path_hdr->next))) {
        ast_str_append(path_str, 0, ",%.*s", (int)path_hdr->hvalue.slen, path_hdr->hvalue.ptr);
    }
 
    return 0;
}
 
static int registrar_validate_path(pjsip_rx_data *rdata, struct ast_sip_aor *aor, struct ast_str **path_str)
{
    const pj_str_t path_supported_name = { "path", 4 };
    pjsip_supported_hdr *supported_hdr;
    int i;
 
    if (!aor->support_path) {
        return 0;
    }
 
    if (build_path_data(rdata, path_str)) {
        return -1;
    }
 
    if (!*path_str) {
        return 0;
    }
 
    supported_hdr = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_SUPPORTED, NULL);
    if (!supported_hdr) {
        return -1;
    }
 
    /* Find advertised path support */
    for (i = 0; i < supported_hdr->count; i++) {
        if (!pj_stricmp(&supported_hdr->values[i], &path_supported_name)) {
            return 0;
        }
    }
 
    /* Path header present, but support not advertised */
    return -1;
}
 
/*! Transport monitor for incoming REGISTER contacts */
struct contact_transport_monitor {
    /*!
     * \brief Sorcery contact name to remove on transport shutdown
     * \note Stored after aor_name in space reserved when struct allocated.
     */
    char *contact_name;
    /*! Indicates that the monitor is in the process of removing a contact */
    int removing;
    /*! AOR name the contact is associated */
    char aor_name[0];
};
 
static int contact_transport_monitor_matcher(void *a, void *b)
{
    struct contact_transport_monitor *ma = a;
    struct contact_transport_monitor *mb = b;
 
    return strcmp(ma->aor_name, mb->aor_name) == 0
        && strcmp(ma->contact_name, mb->contact_name) == 0;
}
 
static int register_contact_transport_remove_cb(void *data)
{
    struct contact_transport_monitor *monitor = data;
    struct ast_sip_contact *contact;
    struct ast_sip_aor *aor;
 
    aor = ast_sip_location_retrieve_aor(monitor->aor_name);
    if (!aor) {
        ao2_lock(monitor);
        monitor->removing = 0;
        ao2_unlock(monitor);
        ao2_ref(monitor, -1);
        return 0;
    }
 
    ao2_lock(aor);
 
    contact = ast_sip_location_retrieve_contact(monitor->contact_name);
    if (contact) {
        registrar_contact_delete(CONTACT_DELETE_SHUTDOWN, NULL, contact, monitor->aor_name);
        ao2_ref(contact, -1);
    }
    ao2_unlock(aor);
    ao2_ref(aor, -1);
 
    ao2_ref(monitor, -1);
    return 0;
}
 
/*!
 * \internal
 * \brief The reliable transport we registered as a contact has shutdown.
 *
 * \param data What contact needs to be removed.
 *
 * \note Normally executed by the pjsip monitor thread.
 */
static void register_contact_transport_shutdown_cb(void *data)
{
    struct contact_transport_monitor *monitor = data;
 
    /*
     * It's possible for this shutdown handler to get called multiple times for the
     * same monitor from different threads. Only one of the calls needs to do the
     * actual removing of the contact, so if one is currently removing then any
     * subsequent calls can skip.
     */
    ao2_lock(monitor);
    if (monitor->removing) {
        ao2_unlock(monitor);
        return;
    }
 
    monitor->removing = 1;
 
    /*
     * Push off to a default serializer.  This is in case sorcery
     * does database accesses for contacts.  Database accesses may
     * not be on this machine.  We don't want to tie up the pjsip
     * monitor thread with potentially long access times.
     */
    ao2_ref(monitor, +1);
    if (ast_sip_push_task(NULL, register_contact_transport_remove_cb, monitor)) {
        monitor->removing = 0;
        ao2_ref(monitor, -1);
    }
 
    ao2_unlock(monitor);
}
 
 
static int registrar_contact_delete(enum contact_delete_type type, pjsip_transport *transport,
    struct ast_sip_contact *contact, const char *aor_name)
{
    int aor_size;
 
    /* Permanent contacts can't be deleted */
    if (ast_tvzero(contact->expiration_time)) {
        return -1;
    }
 
    aor_size = aor_name ? strlen(aor_name) : 0;
    if (contact->prune_on_boot && type != CONTACT_DELETE_SHUTDOWN && aor_size) {
        const char *contact_name = ast_sorcery_object_get_id(contact);
        size_t contact_name_len = strlen(contact_name) + 1;
        struct contact_transport_monitor *monitor = ast_alloca(
            sizeof(*monitor) + 1 + aor_size + contact_name_len);
 
        strcpy(monitor->aor_name, aor_name); /* Safe */
        monitor->contact_name = monitor->aor_name + aor_size + 1;
        ast_copy_string(monitor->contact_name, contact_name, contact_name_len); /* Safe */
 
        if (transport) {
            ast_sip_transport_monitor_unregister(transport,
                register_contact_transport_shutdown_cb, monitor,
                contact_transport_monitor_matcher);
        } else {
            /*
             * If a specific transport is not supplied then unregister the matching
             * monitor from all reliable transports.
             */
            ast_sip_transport_monitor_unregister_all(register_contact_transport_shutdown_cb,
                monitor, contact_transport_monitor_matcher);
        }
    }
 
    ast_sip_location_delete_contact(contact);
 
    if (aor_size) {
        if (VERBOSITY_ATLEAST(3)) {
            const char *reason = "none";
 
            switch (type) {
            case CONTACT_DELETE_ERROR:
                reason = "registration failure";
                break;
            case CONTACT_DELETE_EXISTING:
                reason = "remove existing";
                break;
            case CONTACT_DELETE_UNAVAILABLE:
                reason = "remove unavailable";
                break;
            case CONTACT_DELETE_EXPIRE:
                reason = "expiration";
                break;
            case CONTACT_DELETE_REQUEST:
                reason = "request";
                break;
            case CONTACT_DELETE_SHUTDOWN:
                reason = "shutdown";
                break;
            }
 
            ast_verb(3, "Removed contact '%s' from AOR '%s' due to %s\n",
                     contact->uri, aor_name, reason);
        }
 
        ast_test_suite_event_notify("AOR_CONTACT_REMOVED",
                "Contact: %s\r\n"
                "AOR: %s\r\n"
                "UserAgent: %s",
                contact->uri,
                aor_name,
                contact->user_agent);
    }
 
    return 0;
}
 
AST_VECTOR(excess_contact_vector, struct ast_sip_contact *);
 
static int vec_contact_cmp(struct ast_sip_contact *left, struct ast_sip_contact *right)
{
    struct ast_sip_contact *left_contact = left;
    struct ast_sip_contact *right_contact = right;
 
    /* Sort from soonest to expire to last to expire */
    int time_sorted = ast_tvcmp(left_contact->expiration_time, right_contact->expiration_time);
 
    struct ast_sip_aor *aor = ast_sip_location_retrieve_aor(left_contact->aor);
    struct ast_sip_contact_status *left_status;
    struct ast_sip_contact_status *right_status;
    int remove_unavailable = 0;
    int left_unreachable;
    int right_unreachable;
 
    if (aor) {
        remove_unavailable = aor->remove_unavailable;
        ao2_ref(aor, -1);
    }
 
    if (!remove_unavailable) {
        return time_sorted;
    }
 
    /* Get contact status if available */
    left_status = ast_sip_get_contact_status(left_contact);
    if (!left_status) {
        return time_sorted;
    }
 
    right_status = ast_sip_get_contact_status(right_contact);
    if (!right_status) {
        ao2_ref(left_status, -1);
        return time_sorted;
    }
 
    left_unreachable = (left_status->status == UNAVAILABLE);
    right_unreachable = (right_status->status == UNAVAILABLE);
    ao2_ref(left_status, -1);
    ao2_ref(right_status, -1);
    if (left_unreachable != right_unreachable) {
        /* Set unavailable contact to top of vector */
        if (left_unreachable) return -1;
        if (right_unreachable) return 1;
    }
 
    /* Either both available or both unavailable */
    return time_sorted;
}
 
static int vec_contact_add(void *obj, void *arg, int flags)
{
    struct ast_sip_contact *contact = obj;
    struct excess_contact_vector *contact_vec = arg;
 
    /*
     * Performance wise, an insertion sort is fine because we
     * shouldn't need to remove more than a handful of contacts.
     * I expect we'll typically be removing only one contact.
     */
    AST_VECTOR_ADD_SORTED(contact_vec, contact, vec_contact_cmp);
    if (AST_VECTOR_SIZE(contact_vec) == AST_VECTOR_MAX_SIZE(contact_vec)) {
        /*
         * We added a contact over the number we need to remove.
         * Remove the longest to expire contact from the vector
         * which is the last element in the vector.  It may be
         * the one we just added or the one we just added pushed
         * out an earlier contact from removal consideration.
         */
        --AST_VECTOR_SIZE(contact_vec);
    }
    return 0;
}
 
/*!
 * \internal
 * \brief Remove excess existing contacts that are unavailable or expire soonest.
 * \since 13.18.0
 *
 * \param contacts Container of unmodified contacts that could remove.
 * \param to_remove Maximum number of contacts to remove.
 * \param response_contacts, remove_existing
 */
static void remove_excess_contacts(struct ao2_container *contacts, struct ao2_container *response_contacts,
    unsigned int to_remove, unsigned int remove_existing)
{
    struct excess_contact_vector contact_vec;
 
    /*
     * Create a sorted vector to hold the to_remove soonest to
     * expire contacts.  The vector has an extra space to
     * temporarily hold the longest to expire contact that we
     * won't remove.
     */
    if (AST_VECTOR_INIT(&contact_vec, to_remove + 1)) {
        return;
    }
    ao2_callback(contacts, OBJ_NODATA | OBJ_MULTIPLE, vec_contact_add, &contact_vec);
 
    /*
     * The vector should always be populated with the number
     * of contacts we need to remove.  Just in case, we will
     * remove all contacts in the vector even if the contacts
     * container had fewer contacts than there should be.
     */
    ast_assert(AST_VECTOR_SIZE(&contact_vec) == to_remove);
    to_remove = AST_VECTOR_SIZE(&contact_vec);
 
    /* Remove the excess contacts that are unavailable or expire the soonest */
    while (to_remove--) {
        struct ast_sip_contact *contact;
 
        contact = AST_VECTOR_GET(&contact_vec, to_remove);
 
        if (!remove_existing) {
            registrar_contact_delete(CONTACT_DELETE_UNAVAILABLE, NULL, contact, contact->aor);
        } else {
            registrar_contact_delete(CONTACT_DELETE_EXISTING, NULL, contact, contact->aor);
        }
 
        ao2_unlink(response_contacts, contact);
    }
 
    AST_VECTOR_FREE(&contact_vec);
}
 
/*! \brief Callback function which adds non-permanent contacts to a container */
static int registrar_add_non_permanent(void *obj, void *arg, int flags)
{
    struct ast_sip_contact *contact = obj;
    struct ao2_container *container = arg;
 
    if (ast_tvzero(contact->expiration_time)) {
        return 0;
    }
 
    ao2_link(container, contact);
 
    return 0;
}
 
/*! \brief Internal callback function which adds any contact which is unreachable */
static int registrar_add_unreachable(void *obj, void *arg, int flags)
{
    struct ast_sip_contact *contact = obj;
    struct ao2_container *container = arg;
    struct ast_sip_contact_status *status;
    int unreachable;
 
    status = ast_sip_get_contact_status(contact);
    if (!status) {
        return 0;
    }
 
    unreachable = (status->status == UNAVAILABLE);
    ao2_ref(status, -1);
 
    if (unreachable) {
        ao2_link(container, contact);
    }
 
    return 0;
}
 
struct aor_core_response {
    /*! Tx data to use for statefull response.  NULL for stateless response. */
    pjsip_tx_data *tdata;
    /*! SIP response code to send in stateless response */
    int code;
};
 
static void register_aor_core(pjsip_rx_data *rdata,
    struct ast_sip_endpoint *endpoint,
    struct ast_sip_aor *aor,
    const char *aor_name,
    struct ao2_container *contacts,
    struct aor_core_response *response)
{
    static const pj_str_t USER_AGENT = { "User-Agent", 10 };
 
    int added = 0;
    int updated = 0;
    int deleted = 0;
    int permanent = 0;
    int contact_count;
    struct ao2_container *existing_contacts = NULL;
    struct ao2_container *unavail_contacts = NULL;
    pjsip_contact_hdr *contact_hdr = (pjsip_contact_hdr *)&rdata->msg_info.msg->hdr;
    struct registrar_contact_details details = { 0, };
    pjsip_tx_data *tdata;
    RAII_VAR(struct ast_str *, path_str, NULL, ast_free);
    struct ast_sip_contact *response_contact;
    char *user_agent = NULL;
    pjsip_user_agent_hdr *user_agent_hdr;
    pjsip_expires_hdr *expires_hdr;
    pjsip_via_hdr *via_hdr;
    pjsip_via_hdr *via_hdr_last;
    char *via_addr = NULL;
    int via_port = 0;
    pjsip_cid_hdr *call_id_hdr;
    char *call_id = NULL;
    size_t alloc_size;
 
    /* We create a single pool and use it throughout this function where we need one */
    details.pool = pjsip_endpt_create_pool(ast_sip_get_pjsip_endpoint(),
        "Contact Comparison", 1024, 256);
    if (!details.pool) {
        response->code = 500;
        return;
    }
 
    /* If there are any permanent contacts configured on the AOR we need to take them
     * into account when counting contacts.
     */
    if (aor->permanent_contacts) {
        permanent = ao2_container_count(aor->permanent_contacts);
    }
 
    if (registrar_validate_contacts(rdata, details.pool, contacts, aor, permanent, &added, &updated, &deleted)) {
        /* The provided Contact headers do not conform to the specification */
        ast_sip_report_failed_acl(endpoint, rdata, "registrar_invalid_contacts_provided");
        ast_log(LOG_WARNING, "Failed to validate contacts in REGISTER request from '%s'\n",
                ast_sorcery_object_get_id(endpoint));
        response->code = 400;
        pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
        return;
    }
 
    if (registrar_validate_path(rdata, aor, &path_str)) {
        /* Ensure that intervening proxies did not make invalid modifications to the request */
        ast_log(LOG_WARNING, "Invalid modifications made to REGISTER request from '%s' by intervening proxy\n",
                ast_sorcery_object_get_id(endpoint));
        response->code = 420;
        pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
        return;
    }
 
    if (aor->remove_existing) {
        /* Cumulative number of contacts affected by this registration */
        contact_count = MAX(updated + added - deleted,  0);
 
        /* We need to keep track of only existing contacts so we can later
         * remove them if need be.
         */
        existing_contacts = ao2_container_alloc_list(AO2_ALLOC_OPT_LOCK_NOLOCK, 0,
            NULL, ast_sorcery_object_id_compare);
        if (!existing_contacts) {
            response->code = 500;
            pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
            return;
        }
 
        ao2_callback(contacts, OBJ_NODATA, registrar_add_non_permanent, existing_contacts);
    } else {
        /* Total contacts after this registration */
        contact_count = ao2_container_count(contacts) - permanent + added - deleted;
    }
 
    if (contact_count > aor->max_contacts && aor->remove_unavailable) {
        /* Get unavailable contact total */
        int unavail_count = 0;
 
        unavail_contacts = ao2_container_alloc_list(AO2_ALLOC_OPT_LOCK_NOLOCK, 0,
            NULL, ast_sorcery_object_id_compare);
        if (!unavail_contacts) {
            response->code = 500;
            pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
            return;
        }
        ao2_callback(contacts, OBJ_NODATA, registrar_add_unreachable, unavail_contacts);
        if (unavail_contacts) {
            unavail_count = ao2_container_count(unavail_contacts);
        }
 
        /* Check to see if removing unavailable contacts will help */
        if (contact_count - unavail_count <= aor->max_contacts) {
            /* Remove any unavailable contacts */
            remove_excess_contacts(unavail_contacts, contacts, contact_count - aor->max_contacts, aor->remove_existing);
            ao2_cleanup(unavail_contacts);
            /* We're only here if !aor->remove_existing so this count is correct */
            contact_count = ao2_container_count(contacts) - permanent + added - deleted;
        }
    }
 
    if (contact_count > aor->max_contacts) {
        /* Enforce the maximum number of contacts */
        ast_sip_report_failed_acl(endpoint, rdata, "registrar_attempt_exceeds_maximum_configured_contacts");
        ast_log(LOG_WARNING, "Registration attempt from endpoint '%s' (%s:%d) to AOR '%s' will exceed max contacts of %u\n",
                ast_sorcery_object_get_id(endpoint), rdata->pkt_info.src_name, rdata->pkt_info.src_port,
                aor_name, aor->max_contacts);
        response->code = 403;
        pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
        ao2_cleanup(existing_contacts);
        return;
    }
 
    user_agent_hdr = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &USER_AGENT, NULL);
    if (user_agent_hdr) {
        alloc_size = pj_strlen(&user_agent_hdr->hvalue) + 1;
        user_agent = ast_alloca(alloc_size);
        ast_copy_pj_str(user_agent, &user_agent_hdr->hvalue, alloc_size);
    }
 
    /* Find the first Via header */
    via_hdr = via_hdr_last = (pjsip_via_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_VIA, NULL);
    if (via_hdr) {
        /* Find the last Via header */
        while ( (via_hdr = (pjsip_via_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg,
                PJSIP_H_VIA, via_hdr->next)) != NULL) {
            via_hdr_last = via_hdr;
        }
        alloc_size = pj_strlen(&via_hdr_last->sent_by.host) + 1;
        via_addr = ast_alloca(alloc_size);
        ast_copy_pj_str(via_addr, &via_hdr_last->sent_by.host, alloc_size);
        via_port=via_hdr_last->sent_by.port;
    }
 
    call_id_hdr = (pjsip_cid_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CALL_ID, NULL);
    if (call_id_hdr) {
        alloc_size = pj_strlen(&call_id_hdr->id) + 1;
        call_id = ast_alloca(alloc_size);
        ast_copy_pj_str(call_id, &call_id_hdr->id, alloc_size);
    }
 
    /* Iterate each provided Contact header and add, update, or delete */
    for (; (contact_hdr = (pjsip_contact_hdr *) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, contact_hdr->next)); pj_pool_reset(details.pool)) {
        int expiration;
        char contact_uri[pjsip_max_url_size];
        RAII_VAR(struct ast_sip_contact *, contact, NULL, ao2_cleanup);
 
        if (contact_hdr->star) {
            /* A star means to unregister everything, so do so for the possible contacts */
            ao2_callback(contacts, OBJ_NODATA | OBJ_UNLINK | OBJ_MULTIPLE,
                registrar_delete_contact, (void *)aor_name);
            /* If we are keeping track of existing contacts for removal then, well, there is
             * absolutely nothing left so no need to try to remove any.
             */
            if (existing_contacts) {
                ao2_ref(existing_contacts, -1);
                existing_contacts = NULL;
            }
            break;
        }
 
        if (!PJSIP_URI_SCHEME_IS_SIP(contact_hdr->uri) && !PJSIP_URI_SCHEME_IS_SIPS(contact_hdr->uri)) {
            /* This registrar only currently supports sip: and sips: URI schemes */
            continue;
        }
 
        expiration = registrar_get_expiration(aor, contact_hdr, rdata);
        details.uri = pjsip_uri_get_uri(contact_hdr->uri);
        pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, details.uri, contact_uri, sizeof(contact_uri));
 
        contact = ao2_callback(contacts, OBJ_UNLINK, registrar_find_contact, &details);
 
        /* If a contact was returned and we need to keep track of existing contacts then it
         * should be removed.
         */
        if (contact && existing_contacts) {
            ao2_unlink(existing_contacts, contact);
        }
 
        if (!contact) {
            int prune_on_boot;
 
            /* If they are actually trying to delete a contact that does not exist... be forgiving */
            if (!expiration) {
                ast_verb(3, "Attempted to remove non-existent contact '%s' from AOR '%s' by request\n",
                    contact_uri, aor_name);
                continue;
            }
 
            prune_on_boot = !ast_sip_will_uri_survive_restart(details.uri, endpoint, rdata);
 
            contact = ast_sip_location_create_contact(aor, contact_uri,
                ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1)),
                path_str ? ast_str_buffer(path_str) : NULL,
                user_agent, via_addr, via_port, call_id, prune_on_boot, endpoint);
            if (!contact) {
                ast_log(LOG_ERROR, "Unable to bind contact '%s' to AOR '%s'\n",
                    contact_uri, aor_name);
                continue;
            }
 
            if (prune_on_boot) {
                size_t contact_name_len;
                const char *contact_name;
                struct contact_transport_monitor *monitor;
 
                /*
                 * Monitor the transport in case it gets disconnected because
                 * the contact won't be valid anymore if that happens.
                 */
                contact_name = ast_sorcery_object_get_id(contact);
                contact_name_len = strlen(contact_name) + 1;
                monitor = ao2_alloc(sizeof(*monitor) + 1 + strlen(aor_name)
                    + contact_name_len, NULL);
                if (monitor) {
                    strcpy(monitor->aor_name, aor_name);/* Safe */
                    monitor->contact_name = monitor->aor_name + strlen(aor_name) + 1;
                    ast_copy_string(monitor->contact_name, contact_name, contact_name_len);/* Safe */
 
                    ast_sip_transport_monitor_register_replace(rdata->tp_info.transport,
                        register_contact_transport_shutdown_cb, monitor, contact_transport_monitor_matcher);
                    ao2_ref(monitor, -1);
                }
            }
 
            ast_verb(3, "Added contact '%s' to AOR '%s' with expiration of %d seconds\n",
                contact_uri, aor_name, expiration);
            ast_test_suite_event_notify("AOR_CONTACT_ADDED",
                    "Contact: %s\r\n"
                    "AOR: %s\r\n"
                    "Expiration: %d\r\n"
                    "UserAgent: %s",
                    contact_uri,
                    aor_name,
                    expiration,
                    user_agent);
 
            ao2_link(contacts, contact);
        } else if (expiration) {
            struct ast_sip_contact *contact_update;
 
            contact_update = ast_sorcery_copy(ast_sip_get_sorcery(), contact);
            if (!contact_update) {
                ast_log(LOG_ERROR, "Failed to update contact '%s' expiration time to %d seconds.\n",
                    contact->uri, expiration);
                continue;
            }
 
            contact_update->expiration_time = ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1));
            contact_update->qualify_frequency = aor->qualify_frequency;
            contact_update->authenticate_qualify = aor->authenticate_qualify;
            if (path_str) {
                ast_string_field_set(contact_update, path, ast_str_buffer(path_str));
            }
            if (user_agent) {
                ast_string_field_set(contact_update, user_agent, user_agent);
            }
            if (!ast_strlen_zero(ast_config_AST_SYSTEM_NAME)) {
                ast_string_field_set(contact_update, reg_server, ast_config_AST_SYSTEM_NAME);
            }
 
            if (ast_sip_location_update_contact(contact_update)) {
                ast_log(LOG_ERROR, "Failed to update contact '%s' expiration time to %d seconds.\n",
                    contact->uri, expiration);
                registrar_contact_delete(CONTACT_DELETE_ERROR, rdata->tp_info.transport,
                    contact, aor_name);
                continue;
            }
            ast_debug(3, "Refreshed contact '%s' on AOR '%s' with new expiration of %d seconds\n",
                contact_uri, aor_name, expiration);
            ast_test_suite_event_notify("AOR_CONTACT_REFRESHED",
                    "Contact: %s\r\n"
                    "AOR: %s\r\n"
                    "Expiration: %d\r\n"
                    "UserAgent: %s",
                    contact_uri,
                    aor_name,
                    expiration,
                    contact_update->user_agent);
            ao2_link(contacts, contact_update);
            ao2_cleanup(contact_update);
        } else {
            registrar_contact_delete(CONTACT_DELETE_REQUEST, rdata->tp_info.transport,
                    contact, aor_name);
        }
    }
 
    pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
 
    /*
     * If the AOR is configured to remove any contacts over max_contacts
     * that have not been updated/added/deleted as a result of this
     * REGISTER do so.
     *
     * The existing contacts container holds all contacts that were not
     * involved in this REGISTER.
     * The contacts container holds the current contacts of the AOR.
     */
    if (aor->remove_existing && existing_contacts) {
        /* Total contacts after this registration */
        contact_count = ao2_container_count(existing_contacts) + updated + added;
        if (contact_count > aor->max_contacts) {
            /* Remove excess existing contacts that are unavailable or expire soonest */
            remove_excess_contacts(existing_contacts, contacts, contact_count - aor->max_contacts,
                aor->remove_existing);
        }
        ao2_ref(existing_contacts, -1);
    }
 
    response_contact = ao2_callback(contacts, 0, NULL, NULL);
 
    /* Send a response containing all of the contacts (including static) that are present on this AOR */
    if (ast_sip_create_response(rdata, 200, response_contact, &tdata) != PJ_SUCCESS) {
        ao2_cleanup(response_contact);
        ao2_cleanup(contacts);
        response->code = 500;
        return;
    }
    ao2_cleanup(response_contact);
 
    /* Add the date header to the response, some UAs use this to set their date and time */
    ast_sip_add_date_header(tdata);
 
    ao2_callback(contacts, 0, registrar_add_contact, tdata);
 
    if ((expires_hdr = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_EXPIRES, NULL))) {
        expires_hdr = pjsip_expires_hdr_create(tdata->pool, registrar_get_expiration(aor, NULL, rdata));
        pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)expires_hdr);
    }
 
    response->tdata = tdata;
}
 
static int register_aor(pjsip_rx_data *rdata,
    struct ast_sip_endpoint *endpoint,
    struct ast_sip_aor *aor,
    const char *aor_name)
{
    struct aor_core_response response = {
        .code = 500,
    };
    struct ao2_container *contacts = NULL;
 
    ao2_lock(aor);
    contacts = ast_sip_location_retrieve_aor_contacts_nolock(aor);
    if (!contacts) {
        ao2_unlock(aor);
        pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(),
            rdata, response.code, NULL, NULL, NULL);
        return PJ_TRUE;
    }
 
    register_aor_core(rdata, endpoint, aor, aor_name, contacts, &response);
    ao2_cleanup(contacts);
    ao2_unlock(aor);
 
    /* Now send the REGISTER response to the peer */
    if (response.tdata) {
        ast_sip_send_stateful_response(rdata, response.tdata, endpoint);
    } else {
        pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(),
            rdata, response.code, NULL, NULL, NULL);
    }
    return PJ_TRUE;
}
 
static int match_aor(const char *aor_name, const char *id)
{
    if (ast_strlen_zero(aor_name)) {
        return 0;
    }
 
    if (!strcmp(aor_name, id)) {
        ast_debug(3, "Matched id '%s' to aor '%s'\n", id, aor_name);
        return 1;
    }
 
    return 0;
}
 
static char *find_aor_name(const pj_str_t *pj_username, const pj_str_t *pj_domain, const char *aors)
{
    char *configured_aors;
    char *aors_buf;
    char *aor_name;
    char *id_domain;
    char *username, *domain;
    struct ast_sip_domain_alias *alias;
 
    /* Turn these into C style strings for convenience */
    username = ast_alloca(pj_strlen(pj_username) + 1);
    ast_copy_pj_str(username, pj_username, pj_strlen(pj_username) + 1);
    domain = ast_alloca(pj_strlen(pj_domain) + 1);
    ast_copy_pj_str(domain, pj_domain, pj_strlen(pj_domain) + 1);
 
    id_domain = ast_alloca(strlen(username) + strlen(domain) + 2);
    sprintf(id_domain, "%s@%s", username, domain);
 
    aors_buf = ast_strdupa(aors);
 
    /* Look for exact match on username@domain */
    configured_aors = aors_buf;
    while ((aor_name = ast_strip(strsep(&configured_aors, ",")))) {
        if (match_aor(aor_name, id_domain)) {
            return ast_strdup(aor_name);
        }
    }
 
    /* If there's a domain alias, look for exact match on username@domain_alias */
    alias = ast_sorcery_retrieve_by_id(ast_sip_get_sorcery(), "domain_alias", domain);
    if (alias) {
        char *id_domain_alias = ast_alloca(strlen(username) + strlen(alias->domain) + 2);
 
        sprintf(id_domain_alias, "%s@%s", username, alias->domain);
        ao2_cleanup(alias);
 
        configured_aors = strcpy(aors_buf, aors);/* Safe */
        while ((aor_name = ast_strip(strsep(&configured_aors, ",")))) {
            if (match_aor(aor_name, id_domain_alias)) {
                return ast_strdup(aor_name);
            }
        }
    }
 
    if (ast_strlen_zero(username)) {
        /* No username, no match */
        return NULL;
    }
 
    /* Look for exact match on username only */
    configured_aors = strcpy(aors_buf, aors);/* Safe */
    while ((aor_name = ast_strip(strsep(&configured_aors, ",")))) {
        if (match_aor(aor_name, username)) {
            return ast_strdup(aor_name);
        }
    }
 
    return NULL;
}
 
static struct ast_sip_aor *find_registrar_aor(struct pjsip_rx_data *rdata, struct ast_sip_endpoint *endpoint)
{
    struct ast_sip_aor *aor = NULL;
    char *aor_name = NULL;
    int i;
 
    for (i = 0; i < AST_VECTOR_SIZE(&endpoint->ident_method_order); ++i) {
        pj_str_t username;
        pjsip_sip_uri *uri;
        pjsip_authorization_hdr *header = NULL;
 
        switch (AST_VECTOR_GET(&endpoint->ident_method_order, i)) {
        case AST_SIP_ENDPOINT_IDENTIFY_BY_USERNAME:
            uri = pjsip_uri_get_uri(rdata->msg_info.to->uri);
 
            pj_strassign(&username, &uri->user);
 
            /*
             * We may want to match without any user options getting
             * in the way.
             *
             * Logic adapted from AST_SIP_USER_OPTIONS_TRUNCATE_CHECK for pj_str_t.
             */
            if (ast_sip_get_ignore_uri_user_options()) {
                pj_ssize_t semi = pj_strcspn2(&username, ";");
                if (semi < pj_strlen(&username)) {
                    username.slen = semi;
                }
            }
 
            aor_name = find_aor_name(&username, &uri->host, endpoint->aors);
            if (aor_name) {
                ast_debug(3, "Matched aor '%s' by To username\n", aor_name);
            }
            break;
        case AST_SIP_ENDPOINT_IDENTIFY_BY_AUTH_USERNAME:
            while ((header = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_AUTHORIZATION,
                header ? header->next : NULL))) {
                if (header && !pj_stricmp2(&header->scheme, "digest")) {
                    aor_name = find_aor_name(&header->credential.digest.username,
                        &header->credential.digest.realm, endpoint->aors);
                    if (aor_name) {
                        ast_debug(3, "Matched aor '%s' by Authentication username\n", aor_name);
                        break;
                    }
                }
            }
            break;
        default:
            continue;
        }
 
        if (aor_name) {
            break;
        }
    }
 
    if (ast_strlen_zero(aor_name) || !(aor = ast_sip_location_retrieve_aor(aor_name))) {
        /* The provided AOR name was not found (be it within the configuration or sorcery itself) */
        pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 404, NULL, NULL, NULL);
        ast_sip_report_req_no_support(endpoint, rdata, "registrar_requested_aor_not_found");
        ast_log(LOG_WARNING, "AOR '%s' not found for endpoint '%s' (%s:%d)\n",
            aor_name ?: "", ast_sorcery_object_get_id(endpoint),
            rdata->pkt_info.src_name, rdata->pkt_info.src_port);
    }
    ast_free(aor_name);
    return aor;
}
 
static pj_bool_t registrar_on_rx_request(struct pjsip_rx_data *rdata)
{
    RAII_VAR(struct ast_sip_endpoint *, endpoint,
         ast_pjsip_rdata_get_endpoint(rdata), ao2_cleanup);
    struct ast_sip_aor *aor;
    const char *aor_name;
 
    if (pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, &pjsip_register_method) || !endpoint) {
        return PJ_FALSE;
    }
 
    if (ast_strlen_zero(endpoint->aors)) {
        /* Short circuit early if the endpoint has no AORs configured on it, which means no registration possible */
        pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 403, NULL, NULL, NULL);
        ast_sip_report_failed_acl(endpoint, rdata, "registrar_attempt_without_configured_aors");
        ast_log(LOG_WARNING, "Endpoint '%s' (%s:%d) has no configured AORs\n", ast_sorcery_object_get_id(endpoint),
            rdata->pkt_info.src_name, rdata->pkt_info.src_port);
        return PJ_TRUE;
    }
 
    if (!PJSIP_URI_SCHEME_IS_SIP(rdata->msg_info.to->uri) && !PJSIP_URI_SCHEME_IS_SIPS(rdata->msg_info.to->uri)) {
        pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 416, NULL, NULL, NULL);
        ast_sip_report_failed_acl(endpoint, rdata, "registrar_invalid_uri_in_to_received");
        ast_log(LOG_WARNING, "Endpoint '%s' (%s:%d) attempted to register to an AOR with a non-SIP URI\n", ast_sorcery_object_get_id(endpoint),
            rdata->pkt_info.src_name, rdata->pkt_info.src_port);
        return PJ_TRUE;
    }
 
    aor = find_registrar_aor(rdata, endpoint);
    if (!aor) {
        /* We've already responded about not finding an AOR. */
        return PJ_TRUE;
    }
 
    aor_name = ast_sorcery_object_get_id(aor);
 
    if (!aor->max_contacts) {
        /* Registration is not permitted for this AOR */
        pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 403, NULL, NULL, NULL);
        ast_sip_report_req_no_support(endpoint, rdata, "registrar_attempt_without_registration_permitted");
        ast_log(LOG_WARNING, "AOR '%s' has no configured max_contacts. Endpoint '%s' (%s:%d) unable to register\n",
            aor_name, ast_sorcery_object_get_id(endpoint),
            rdata->pkt_info.src_name, rdata->pkt_info.src_port);
    } else {
        register_aor(rdata, endpoint, aor, aor_name);
    }
    ao2_ref(aor, -1);
    return PJ_TRUE;
}
 
/* function pointer to callback needs to be within the module
   in order to avoid problems with an undefined symbol */
static int sip_contact_to_str(void *acp, void *arg, int flags)
{
    return ast_sip_contact_to_str(acp, arg, flags);
}
 
static int ami_registrations_aor(void *obj, void *arg, int flags)
{
    struct ast_sip_aor *aor = obj;
    struct ast_sip_ami *ami = arg;
    int *count = ami->arg;
    RAII_VAR(struct ast_str *, buf,
         ast_sip_create_ami_event("InboundRegistrationDetail", ami), ast_free);
 
    if (!buf) {
        return -1;
    }
 
    ast_sip_sorcery_object_to_ami(aor, &buf);
    ast_str_append(&buf, 0, "Contacts: ");
    ast_sip_for_each_contact(aor, sip_contact_to_str, &buf);
    ast_str_append(&buf, 0, "\r\n");
 
    astman_append(ami->s, "%s\r\n", ast_str_buffer(buf));
    (*count)++;
    return 0;
}
 
static int ami_registrations_endpoint(void *obj, void *arg, int flags)
{
    struct ast_sip_endpoint *endpoint = obj;
    return ast_sip_for_each_aor(
        endpoint->aors, ami_registrations_aor, arg);
}
 
static int ami_registrations_endpoints(void *arg)
{
    RAII_VAR(struct ao2_container *, endpoints,
         ast_sip_get_endpoints(), ao2_cleanup);
 
    if (!endpoints) {
        return 0;
    }
 
    ao2_callback(endpoints, OBJ_NODATA, ami_registrations_endpoint, arg);
    return 0;
}
 
static int ami_show_registrations(struct mansession *s, const struct message *m)
{
    int count = 0;
    struct ast_sip_ami ami = { .s = s, .m = m, .arg = &count, .action_id = astman_get_header(m, "ActionID"), };
 
    astman_send_listack(s, m, "Following are Events for each Inbound registration",
        "start");
 
    ami_registrations_endpoints(&ami);
 
    astman_send_list_complete_start(s, m, "InboundRegistrationDetailComplete", count);
    astman_send_list_complete_end(s);
    return 0;
}
 
static int ami_show_registration_contact_statuses(struct mansession *s, const struct message *m)
{
    int count = 0;
    struct ast_sip_ami ami = { .s = s, .m = m, .arg = NULL, .action_id = astman_get_header(m, "ActionID"), };
    struct ao2_container *contacts = ast_sorcery_retrieve_by_fields(
        ast_sip_get_sorcery(), "contact", AST_RETRIEVE_FLAG_MULTIPLE | AST_RETRIEVE_FLAG_ALL, NULL);
    struct ao2_iterator i;
    struct ast_sip_contact *contact;
 
    astman_send_listack(s, m, "Following are ContactStatusEvents for each Inbound "
                "registration", "start");
 
    if (contacts) {
        i = ao2_iterator_init(contacts, 0);
        while ((contact = ao2_iterator_next(&i))) {
            struct ast_sip_contact_wrapper wrapper;
 
            wrapper.aor_id = (char *)contact->aor;
            wrapper.contact = contact;
            wrapper.contact_id = (char *)ast_sorcery_object_get_id(contact);
 
            ast_sip_format_contact_ami(&wrapper, &ami, 0);
            count++;
 
            ao2_ref(contact, -1);
        }
        ao2_iterator_destroy(&i);
        ao2_ref(contacts, -1);
    }
 
    astman_send_list_complete_start(s, m, "ContactStatusDetailComplete", count);
    astman_send_list_complete_end(s);
    return 0;
}
 
#define AMI_SHOW_REGISTRATION_CONTACT_STATUSES "PJSIPShowRegistrationInboundContactStatuses"
#define AMI_SHOW_REGISTRATIONS "PJSIPShowRegistrationsInbound"
 
static pjsip_module registrar_module = {
    .name = { "Registrar", 9 },
    .id = -1,
    .priority = PJSIP_MOD_PRIORITY_APPLICATION,
    .on_rx_request = registrar_on_rx_request,
};
 
/*! \brief Thread keeping things alive */
static pthread_t check_thread = AST_PTHREADT_NULL;
 
/*! \brief The global interval at which to check for contact expiration */
static unsigned int check_interval;
 
/*! \brief Callback function which deletes a contact */
static int expire_contact(void *obj, void *arg, int flags)
{
    struct ast_sip_contact *contact = obj;
    struct ast_named_lock *lock;
 
    lock = ast_named_lock_get(AST_NAMED_LOCK_TYPE_MUTEX, "aor", contact->aor);
    if (!lock) {
        return 0;
    }
 
    /*
     * We need to check the expiration again with the aor lock held
     * in case another thread is attempting to renew the contact.
     */
    ao2_lock(lock);
    if (ast_tvdiff_ms(ast_tvnow(), contact->expiration_time) > 0) {
        registrar_contact_delete(CONTACT_DELETE_EXPIRE, NULL, contact, contact->aor);
    }
    ao2_unlock(lock);
    ast_named_lock_put(lock);
 
    return 0;
}
 
static void *check_expiration_thread(void *data)
{
    struct ao2_container *contacts;
    struct ast_variable *var;
    char time[AST_TIME_T_LEN];
 
    while (check_interval) {
        sleep(check_interval);
 
        ast_time_t_to_string(ast_tvnow().tv_sec, time, sizeof(time));
 
        var = ast_variable_new("expiration_time <=", time, "");
 
        ast_debug(4, "Woke up at %s  Interval: %d\n", time, check_interval);
 
        contacts = ast_sorcery_retrieve_by_fields(ast_sip_get_sorcery(), "contact",
            AST_RETRIEVE_FLAG_MULTIPLE, var);
 
        ast_variables_destroy(var);
        if (contacts) {
            ast_debug(3, "Expiring %d contacts\n", ao2_container_count(contacts));
            ao2_callback(contacts, OBJ_NODATA, expire_contact, NULL);
            ao2_ref(contacts, -1);
        }
    }
 
    return NULL;
}
 
static void expiration_global_loaded(const char *object_type)
{
    check_interval = ast_sip_get_contact_expiration_check_interval();
 
    /* Observer calls are serialized so this is safe without it's own lock */
    if (check_interval) {
        if (check_thread == AST_PTHREADT_NULL) {
            if (ast_pthread_create_background(&check_thread, NULL, check_expiration_thread, NULL)) {
                ast_log(LOG_ERROR, "Could not create thread for checking contact expiration.\n");
                return;
            }
            ast_debug(3, "Interval = %d, starting thread\n", check_interval);
        }
    } else {
        if (check_thread != AST_PTHREADT_NULL) {
            pthread_kill(check_thread, SIGURG);
            pthread_join(check_thread, NULL);
            check_thread = AST_PTHREADT_NULL;
            ast_debug(3, "Interval = 0, shutting thread down\n");
        }
    }
}
 
/*! \brief Observer which is used to update our interval when the global setting changes */
static struct ast_sorcery_observer expiration_global_observer = {
    .loaded = expiration_global_loaded,
};
 
static int load_module(void)
{
    const pj_str_t STR_REGISTER = { "REGISTER", 8 };
 
    ast_pjproject_get_buildopt("PJ_MAX_HOSTNAME", "%d", &pj_max_hostname);
    /* As of pjproject 2.4.5, PJSIP_MAX_URL_SIZE isn't exposed yet but we try anyway. */
    ast_pjproject_get_buildopt("PJSIP_MAX_URL_SIZE", "%d", &pjsip_max_url_size);
 
    if (ast_sip_register_service(&registrar_module)) {
        return AST_MODULE_LOAD_DECLINE;
    }
 
    if (pjsip_endpt_add_capability(ast_sip_get_pjsip_endpoint(), NULL, PJSIP_H_ALLOW, NULL, 1, &STR_REGISTER) != PJ_SUCCESS) {
        ast_sip_unregister_service(&registrar_module);
        return AST_MODULE_LOAD_DECLINE;
    }
 
    ast_manager_register_xml(AMI_SHOW_REGISTRATIONS, EVENT_FLAG_SYSTEM,
                 ami_show_registrations);
    ast_manager_register_xml(AMI_SHOW_REGISTRATION_CONTACT_STATUSES, EVENT_FLAG_SYSTEM,
                 ami_show_registration_contact_statuses);
 
    ast_sorcery_observer_add(ast_sip_get_sorcery(), "global", &expiration_global_observer);
    ast_sorcery_reload_object(ast_sip_get_sorcery(), "global");
 
    return AST_MODULE_LOAD_SUCCESS;
}
 
static int unload_module(void)
{
    if (check_thread != AST_PTHREADT_NULL) {
        check_interval = 0;
        pthread_kill(check_thread, SIGURG);
        pthread_join(check_thread, NULL);
 
        check_thread = AST_PTHREADT_NULL;
    }
 
    ast_sorcery_observer_remove(ast_sip_get_sorcery(), "global", &expiration_global_observer);
 
    ast_manager_unregister(AMI_SHOW_REGISTRATIONS);
    ast_manager_unregister(AMI_SHOW_REGISTRATION_CONTACT_STATUSES);
    ast_sip_unregister_service(&registrar_module);
    ast_sip_transport_monitor_unregister_all(register_contact_transport_shutdown_cb, NULL, NULL);
    return 0;
}
 
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP Registrar Support",
    .support_level = AST_MODULE_SUPPORT_CORE,
    .load = load_module,
    .unload = unload_module,
    .load_pri = AST_MODPRI_CHANNEL_DEPEND - 3,
    .requires = "res_pjproject,res_pjsip",
);