res_pjsip_geolocation.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2022, Sangoma Technologies Corporation
 *
 * George Joseph <gjoseph@sangoma.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>res_geolocation</depend>
    <depend>pjproject</depend>
    <depend>res_pjsip</depend>
    <depend>res_pjsip_session</depend>
    <depend>chan_pjsip</depend>
    <depend>libxml2</depend>
    <support_level>core</support_level>
 ***/
 
#include "asterisk.h"
#include "asterisk/module.h"
#include "asterisk/xml.h"
#include "asterisk/res_geolocation.h"
 
#include <pjsip_ua.h>
#include "asterisk/res_pjsip.h"
#include "asterisk/res_pjsip_session.h"
 
static pj_str_t GEOLOCATION_HDR;
static pj_str_t GEOLOCATION_ROUTING_HDR;
 
static int find_pidf(const char *session_name, struct pjsip_rx_data *rdata, char *geoloc_uri,
    char **pidf_body, unsigned int *pidf_len)
{
    char *local_uri = ast_strdupa(geoloc_uri);
    char *ra = NULL;
    /*
     * If the URI is "cid" then we're going to search for a pidf document
     * in the body of the message.  If there's no body, there's no point.
     */
    if (!rdata->msg_info.msg->body) {
        ast_log(LOG_WARNING, "%s: There's no message body in which to search for '%s'.  Skipping\n",
            session_name, geoloc_uri);
        return -1;
    }
 
    if (local_uri[0] == '<') {
        local_uri++;
    }
    ra = strchr(local_uri, '>');
    if (ra) {
        *ra = '\0';
    }
 
    /*
     * If the message content type is 'application/pidf+xml', then the pidf is
     * the only document in the message and we'll just parse the entire body
     * as xml.  If it's 'multipart/mixed' then we have to find the part that
     * has a Content-ID header value matching the URI.
     */
    if (ast_sip_are_media_types_equal(&rdata->msg_info.ctype->media,
        &pjsip_media_type_application_pidf_xml)) {
        *pidf_body = rdata->msg_info.msg->body->data;
        *pidf_len = rdata->msg_info.msg->body->len;
    } else if (ast_sip_are_media_types_equal(&rdata->msg_info.ctype->media,
        &pjsip_media_type_multipart_mixed)) {
        pj_str_t cid = pj_str(local_uri);
        pjsip_multipart_part *mp = pjsip_multipart_find_part_by_cid_str(
            rdata->tp_info.pool, rdata->msg_info.msg->body, &cid);
 
        if (!mp) {
            ast_log(LOG_WARNING, "%s: A Geolocation header was found with URI '%s'"
                " but the associated multipart part was not found in the message body.  Skipping URI",
                session_name, geoloc_uri);
            return -1;
        }
        *pidf_body = mp->body->data;
        *pidf_len = mp->body->len;
    } else {
        ast_log(LOG_WARNING, "%s: A Geolocation header was found with URI '%s'"
            " but no pidf document with that content id was found.  Skipping URI",
            session_name, geoloc_uri);
        return -1;
    }
 
    return 0;
}
 
static int add_eprofile_to_channel(struct ast_sip_session *session,
    struct ast_geoloc_eprofile *eprofile, struct ast_str * buf)
{
    const char *session_name = (session ? ast_sip_session_get_name(session) : "NULL_SESSION");
    struct ast_datastore *ds = NULL;
    int rc = 0;
    SCOPE_ENTER(4, "%s\n", session_name);
 
    ds = ast_geoloc_datastore_create(session_name);
    if (!ds) {
        SCOPE_EXIT_LOG_RTN_VALUE(-1, LOG_WARNING,
            "%s: Couldn't allocate a geoloc datastore\n", session_name);
    }
 
    /*
     * We want the datastore to pass through the dialplan and the core
     * so we need to turn inheritance on.
     */
    ast_geoloc_datastore_set_inheritance(ds, 1);
 
    rc = ast_geoloc_datastore_add_eprofile(ds, eprofile);
    if (rc <= 0) {
        ast_datastore_free(ds);
        SCOPE_EXIT_LOG_RTN_VALUE(-1, LOG_WARNING,
            "%s: Couldn't add eprofile '%s' to datastore\n", session_name,
            eprofile->id);
    }
 
    ast_channel_lock(session->channel);
    ast_channel_datastore_add(session->channel, ds);
    ast_channel_unlock(session->channel);
 
    SCOPE_EXIT_RTN_VALUE(0, "%s: eprofile: '%s' EffectiveLoc: %s\n",
        session_name, eprofile->id, ast_str_buffer(
        ast_variable_list_join(eprofile->effective_location, ",", "=", NULL, &buf)));
}
 
static int handle_incoming_request(struct ast_sip_session *session, struct pjsip_rx_data *rdata)
{
    const char *session_name = (session ? ast_sip_session_get_name(session) : "NULL_SESSION");
    struct ast_sip_endpoint *endpoint = (session ? session->endpoint : NULL);
    struct ast_channel *channel = (session ? session->channel : NULL);
    RAII_VAR(struct ast_geoloc_profile *, config_profile, NULL, ao2_cleanup);
    RAII_VAR(struct ast_geoloc_eprofile *, config_eprofile, NULL, ao2_cleanup);
    RAII_VAR(struct ast_datastore *, ds, NULL, ast_datastore_free);
    RAII_VAR(struct ast_geoloc_eprofile *, incoming_eprofile, NULL, ao2_cleanup);
    char *geoloc_hdr_value = NULL;
    char *geoloc_routing_hdr_value = NULL;
    char *geoloc_uri = NULL;
    int rc = 0;
    RAII_VAR(struct ast_str *, buf, NULL, ast_free);
    pjsip_generic_string_hdr *geoloc_hdr = NULL;
    pjsip_generic_string_hdr *geoloc_routing_hdr = NULL;
    SCOPE_ENTER(3, "%s\n", session_name);
 
    if (!session) {
        SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING, "%s: session is NULL!!!.  Skipping.\n",
            session_name);
    }
    if (!endpoint) {
        SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING, "%s: Session has no endpoint.  Skipping.\n",
            session_name);
    }
 
    if (!channel) {
        SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING, "%s: Session has no channel.  Skipping.\n",
            session_name);
    }
 
    if (!rdata) {
        SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING, "%s: Session has no rdata.  Skipping.\n",
            session_name);
    }
 
    /*
     * We don't need geoloc_hdr or geoloc_routing_hdr for a while but we get it now
     * for trace purposes.
     */
    geoloc_hdr = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &GEOLOCATION_HDR, NULL);
    geoloc_routing_hdr = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg,
        &GEOLOCATION_ROUTING_HDR, NULL);
 
    if (!geoloc_hdr) {
        ast_trace(4, "%s: Message has no Geolocation header\n", session_name);
    } else {
        ast_trace(4, "%s: Geolocation: " PJSTR_PRINTF_SPEC "\n", session_name,
            PJSTR_PRINTF_VAR(geoloc_hdr->hvalue));
    }
 
    if (ast_strlen_zero(endpoint->geoloc_incoming_call_profile)) {
        if (geoloc_hdr) {
            SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_NOTICE, "%s: Message has Geolocation header '"
                PJSTR_PRINTF_SPEC "' but endpoint has no geoloc_incoming_call_profile. "
                "Done.\n", session_name,
                PJSTR_PRINTF_VAR(geoloc_hdr->hvalue));
        } else {
            SCOPE_EXIT_RTN_VALUE(0, "%s: Endpoint has no geoloc_incoming_call_profile. "
                "Done.\n", session_name);
        }
    }
 
    config_profile = ast_geoloc_get_profile(endpoint->geoloc_incoming_call_profile);
    if (!config_profile) {
        if (geoloc_hdr) {
            SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_NOTICE, "%s: Message has Geolocation header '"
                PJSTR_PRINTF_SPEC "' but endpoint's geoloc_incoming_call_profile doesn't exist. "
                "Done.\n", session_name,
                PJSTR_PRINTF_VAR(geoloc_hdr->hvalue));
        } else {
            SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_NOTICE, "%s: Message has no Geolocation header and endpoint has "
                " an invalid geoloc_incoming_call_profile. Done.\n", session_name);
        }
    }
 
    buf = ast_str_create(1024);
    if (!buf) {
        SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING, "%s: Unable to allocate buf\n", session_name);
    }
 
    if (config_profile->precedence != AST_GEOLOC_PRECED_DISCARD_CONFIG) {
        config_eprofile = ast_geoloc_eprofile_create_from_profile(config_profile);
        if (!config_eprofile) {
            ast_log(LOG_WARNING, "%s: Unable to create config_eprofile from "
                "profile '%s'\n", session_name, ast_sorcery_object_get_id(config_profile));
        }
 
        if (config_eprofile && config_eprofile->effective_location) {
            ast_trace(4, "%s: config eprofile '%s' has effective location\n",
                session_name, config_eprofile->id);
 
            if (!geoloc_hdr || config_profile->precedence == AST_GEOLOC_PRECED_DISCARD_INCOMING ||
                config_profile->precedence == AST_GEOLOC_PRECED_PREFER_CONFIG) {
 
                ast_trace(4, "%s: config eprofile '%s' is being used\n",
                    session_name, config_eprofile->id);
 
                /*
                 * If we have an effective location and there's no geolocation header,
                 * or the action is either DISCARD_INCOMING or PREFER_CONFIG,
                 * we don't need to even look for a Geolocation header so just add the
                 * config eprofile to the channel and exit.
                 */
 
                rc = add_eprofile_to_channel(session, config_eprofile, buf);
                if (rc != 0) {
                    SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING,
                        "%s: Couldn't add config eprofile '%s' to datastore. Fail.\n", session_name,
                        config_eprofile->id);
                }
 
                SCOPE_EXIT_RTN_VALUE(0, "%s: Added geoloc datastore with eprofile from config. Done.\n",
                    session_name);
            }
        } else {
            /*
             * If the config eprofile has no effective location, just get rid
             * of it.
             */
            ast_trace(4, "%s: Either config_eprofile didn't exist or it had no effective location\n",
                session_name);
 
            ao2_cleanup(config_eprofile);
            config_eprofile = NULL;
            if (config_profile->precedence == AST_GEOLOC_PRECED_DISCARD_INCOMING) {
                SCOPE_EXIT_RTN_VALUE(0, "%s: DISCARD_INCOMING set and no config eprofile. Done.\n",
                    session_name);
            }
        }
    }
 
    /*
     * At this point, if we have a config_eprofile, then the action was
     * PREFER_INCOMING so we're going to keep it as a backup if we can't
     * get a profile from the incoming message.
     */
 
    if (geoloc_hdr && config_profile->precedence != AST_GEOLOC_PRECED_DISCARD_INCOMING) {
 
        /*
         * From RFC-6442:
         * Geolocation-header = "Geolocation" HCOLON locationValue
         *                      *( COMMA locationValue )
         * locationValue      = LAQUOT locationURI RAQUOT
         *                      *(SEMI geoloc-param)
         * locationURI        = sip-URI / sips-URI / pres-URI
         *                        / http-URI / https-URI
         *                        / cid-url ; (from RFC 2392)
         *                        / absoluteURI ; (from RFC 3261)
         */
 
        geoloc_hdr_value = ast_alloca(geoloc_hdr->hvalue.slen + 1);
        ast_copy_pj_str(geoloc_hdr_value, &geoloc_hdr->hvalue, geoloc_hdr->hvalue.slen + 1);
 
        /*
         * We're going to scan the header value for URIs until we find
         * one that processes successfully or we run out of URIs.
         * I.E.  The first good one wins.
         */
        while (geoloc_hdr_value && !incoming_eprofile) {
            char *pidf_body = NULL;
            unsigned int pidf_len = 0;
            struct ast_xml_doc *incoming_doc = NULL;
            int rc = 0;
 
            /* We're only going to consider the first URI in the header for now */
            geoloc_uri = ast_strsep(&geoloc_hdr_value, ',', AST_STRSEP_TRIM);
            if (ast_strlen_zero(geoloc_uri) || geoloc_uri[0] != '<' || strchr(geoloc_uri, '>') == NULL) {
                ast_log(LOG_WARNING, "%s: Geolocation header has no or bad URI '%s'.  Skipping\n", session_name,
                    S_OR(geoloc_uri, "<empty>"));
                continue;
            }
 
            ast_trace(4, "Processing URI '%s'\n", geoloc_uri);
 
            if (!ast_begins_with(geoloc_uri, "<cid:")) {
                ast_trace(4, "Processing URI '%s'\n", geoloc_uri);
 
                incoming_eprofile = ast_geoloc_eprofile_create_from_uri(geoloc_uri, session_name);
                if (!incoming_eprofile) {
                    ast_log(LOG_WARNING, "%s: Unable to create effective profile for URI '%s'.  Skipping\n",
                        session_name, geoloc_uri);
                    continue;
                }
            } else {
                ast_trace(4, "Processing PIDF-LO '%s'\n", geoloc_uri);
 
                rc = find_pidf(session_name, rdata, geoloc_uri, &pidf_body, &pidf_len);
                if (rc != 0 || !pidf_body || pidf_len == 0) {
                    continue;
                }
                ast_trace(5, "Processing PIDF-LO "PJSTR_PRINTF_SPEC "\n", (int)pidf_len, pidf_body);
 
                incoming_doc = ast_xml_read_memory(pidf_body, pidf_len);
                if (!incoming_doc) {
                    ast_log(LOG_WARNING, "%s: Unable to parse pidf document for URI '%s'\n",
                        session_name, geoloc_uri);
                    continue;
                }
 
                incoming_eprofile = ast_geoloc_eprofile_create_from_pidf(incoming_doc, geoloc_uri, session_name);
                ast_xml_close(incoming_doc);
 
                if (!incoming_eprofile) {
                    ast_log(LOG_WARNING,
                        "%s: Couldn't create incoming_eprofile from pidf\n", session_name);
                    continue;
                }
            }
        }
    }
 
    if (!incoming_eprofile) {
        /* Use the config_eprofile as a backup if there was one */
        incoming_eprofile = config_eprofile;
    } else {
        ao2_cleanup(config_eprofile);
        config_eprofile = NULL;
        if (geoloc_routing_hdr) {
            geoloc_routing_hdr_value = ast_alloca(geoloc_routing_hdr->hvalue.slen + 1);
            ast_copy_pj_str(geoloc_routing_hdr_value, &geoloc_routing_hdr->hvalue,
                geoloc_routing_hdr->hvalue.slen + 1);
            incoming_eprofile->allow_routing_use = ast_true(geoloc_routing_hdr_value);
        }
    }
 
    if (incoming_eprofile) {
        rc = add_eprofile_to_channel(session, incoming_eprofile, buf);
        if (rc != 0) {
            SCOPE_EXIT_LOG_RTN_VALUE(0, LOG_WARNING,
                "%s: Couldn't add eprofile '%s' to channel. Fail.\n", session_name,
                incoming_eprofile->id);
        }
 
        SCOPE_EXIT_RTN_VALUE(0, "%s: Added eprofile '%s' to channel. Done.\n",
            session_name, incoming_eprofile->id);
    }
 
    SCOPE_EXIT_RTN_VALUE(0, "%s: No eprofiles to add to channel. Done.\n",  session_name);
}
 
static const char *add_eprofile_to_tdata(struct ast_geoloc_eprofile *eprofile, struct ast_channel *channel,
    struct pjsip_tx_data *tdata, struct ast_str **buf, const char *session_name)
{
    static const pj_str_t from_name = { "From", 4};
    static const pj_str_t cid_name = { "Content-ID", 10 };
 
    pjsip_sip_uri *sip_uri;
    pjsip_generic_string_hdr *cid;
    pj_str_t cid_value;
    pjsip_from_hdr *from = pjsip_msg_find_hdr_by_name(tdata->msg, &from_name, NULL);
    pjsip_sdp_info *tdata_sdp_info;
    pjsip_msg_body *multipart_body = NULL;
    pjsip_multipart_part *pidf_part;
    pj_str_t pidf_body_text;
    char id[6];
    size_t alloc_size;
    RAII_VAR(char *, base_cid, NULL, ast_free);
    const char *final_doc;
    int rc = 0;
    SCOPE_ENTER(3, "%s\n", session_name);
 
    /*
     * ast_geoloc_eprofiles_to_pidf() takes the datastore with all of the eprofiles
     * in it, skips over the ones not needing PIDF processing and combines the
     * rest into one document.
     */
    final_doc = ast_geoloc_eprofile_to_pidf(eprofile, channel, buf, session_name);
    ast_trace(5, "Final pidf: \n%s\n", final_doc);
 
    if (!final_doc) {
        SCOPE_EXIT_LOG_RTN_VALUE(NULL, LOG_ERROR, "%s: Unable to create pidf document from"
            " eprofile '%s'\n\n", session_name, eprofile->id);
    }
 
    /*
     * There _should_ be an SDP already attached to the tdata at this point
     * but maybe not.  If we can find an existing one, we'll convert the tdata
     * body into a multipart body and add the SDP as the first part.  Then we'll
     * create another part to hold the PIDF.
     *
     * If we don't find one, we're going to create an empty multipart body
     * and add the PIDF part to it.
     *
     * Technically, if we only have the PIDF, we don't need a multipart
     * body to hold it but that means we'd have to add the Content-ID header
     * to the main SIP message.  Since it's unlikely, it's just better to
     * add the multipart body and leave the rest of the processing unchanged.
     */
    tdata_sdp_info = pjsip_tdata_get_sdp_info(tdata);
    if (tdata_sdp_info->sdp) {
        ast_trace(4, "body: %p %u\n", tdata_sdp_info->sdp, (unsigned)tdata_sdp_info->sdp_err);
 
        rc = pjsip_create_multipart_sdp_body(tdata->pool, tdata_sdp_info->sdp, &multipart_body);
        if (rc != PJ_SUCCESS) {
            SCOPE_EXIT_LOG_RTN_VALUE(NULL, LOG_ERROR, "%s: Unable to create sdp multipart body\n",
                session_name);
        }
    } else {
        multipart_body = pjsip_multipart_create(tdata->pool, &pjsip_media_type_multipart_mixed, NULL);
    }
 
    pidf_part = pjsip_multipart_create_part(tdata->pool);
    pj_cstr(&pidf_body_text, final_doc);
    pidf_part->body = pjsip_msg_body_create(tdata->pool, &pjsip_media_type_application_pidf_xml.type,
        &pjsip_media_type_application_pidf_xml.subtype, &pidf_body_text);
 
    pjsip_multipart_add_part(tdata->pool, multipart_body, pidf_part);
 
    sip_uri = (pjsip_sip_uri *)pjsip_uri_get_uri(from->uri);
    alloc_size = sizeof(id) + pj_strlen(&sip_uri->host) + 2;
    base_cid = ast_malloc(alloc_size);
    sprintf(base_cid, "%s@%.*s",
            ast_generate_random_string(id, sizeof(id)),
            (int) pj_strlen(&sip_uri->host), pj_strbuf(&sip_uri->host));
 
    ast_str_set(buf, 0, "cid:%s", base_cid);
    ast_trace(4, "cid: '%s' uri: '%s'\n", base_cid, ast_str_buffer(*buf));
 
    cid_value.ptr = pj_pool_alloc(tdata->pool, alloc_size);
    cid_value.slen = sprintf(cid_value.ptr, "<%s>", base_cid);
 
    cid = pjsip_generic_string_hdr_create(tdata->pool, &cid_name, &cid_value);
 
    pj_list_insert_after(&pidf_part->hdr, cid);
 
    tdata->msg->body = multipart_body;
 
    SCOPE_EXIT_RTN_VALUE(ast_str_buffer(*buf), "%s: PIDF-LO added with cid '%s'\n", session_name, base_cid);
}
 
static void handle_outgoing_request(struct ast_sip_session *session, struct pjsip_tx_data *tdata)
{
    const char *session_name = ast_sip_session_get_name(session);
    struct ast_sip_endpoint *endpoint = session->endpoint;
    struct ast_channel *channel = session->channel;
    RAII_VAR(struct ast_geoloc_profile *, config_profile, NULL, ao2_cleanup);
    RAII_VAR(struct ast_geoloc_eprofile *, config_eprofile, NULL, ao2_cleanup);
    RAII_VAR(struct ast_geoloc_eprofile *, incoming_eprofile, NULL, ao2_cleanup);
    struct ast_geoloc_eprofile *final_eprofile = NULL;
    RAII_VAR(struct ast_str *, buf, NULL, ast_free);
    struct ast_datastore *ds = NULL;  /* The channel cleans up ds */
    pjsip_msg_body *orig_body = NULL;
    pjsip_generic_string_hdr *geoloc_hdr = NULL;
    int eprofile_count = 0;
    int rc = 0;
    const char *uri;
    SCOPE_ENTER(3, "%s\n", session_name);
 
    if (!endpoint) {
        SCOPE_EXIT_LOG_RTN(LOG_WARNING, "%s: Session has no endpoint.  Skipping.\n",
            session_name);
    }
 
    if (!channel) {
        SCOPE_EXIT_LOG_RTN(LOG_WARNING, "%s: Session has no channel.  Skipping.\n",
            session_name);
    }
 
    if (ast_strlen_zero(endpoint->geoloc_outgoing_call_profile)) {
        SCOPE_EXIT_RTN("%s: Endpoint has no geoloc_outgoing_call_profile. Skipping.\n",
            session_name);
    }
 
    config_profile = ast_geoloc_get_profile(endpoint->geoloc_outgoing_call_profile);
    if (!config_profile) {
        SCOPE_EXIT_LOG_RTN(LOG_ERROR, "%s: Endpoint's geoloc_outgoing_call_profile doesn't exist. "
            "Geolocation info discarded.\n", session_name);
    }
 
    config_eprofile = ast_geoloc_eprofile_create_from_profile(config_profile);
    if (!config_eprofile) {
        SCOPE_EXIT_LOG_RTN(LOG_WARNING, "%s: Unable to create eprofile from "
            "profile '%s'\n", session_name, ast_sorcery_object_get_id(config_profile));
    }
 
    if (!config_eprofile->effective_location) {
        /*
         * If there's no effective location on the eprofile
         * we don't need to keep it.
         */
        ast_trace(4, "%s: There was no effective location for config profile '%s'\n",
            session_name, ast_sorcery_object_get_id(config_profile));
        ao2_ref(config_eprofile, -1);
        config_eprofile = NULL;
    }
 
    ds = ast_geoloc_datastore_find(channel);
    if (!ds) {
        ast_trace(4, "%s: There was no geoloc datastore on the channel\n", session_name);
    } else {
        eprofile_count = ast_geoloc_datastore_size(ds);
        ast_trace(4, "%s: There are %d geoloc profiles on this channel\n", session_name,
            eprofile_count);
        /*
         * There'd better be a max of 1 at this time.  In the future
         * we may allow more than 1.
         */
        incoming_eprofile = ast_geoloc_datastore_get_eprofile(ds, 0);
    }
 
    ast_trace(4, "%s: Profile precedence: %s\n\n", session_name,
        ast_geoloc_precedence_to_name(config_profile->precedence));
 
    switch (config_profile->precedence) {
    case AST_GEOLOC_PRECED_DISCARD_INCOMING:
        final_eprofile = config_eprofile;
        ao2_cleanup(incoming_eprofile);
        incoming_eprofile = NULL;
        break;
    case AST_GEOLOC_PRECED_PREFER_INCOMING:
        if (incoming_eprofile) {
            final_eprofile = incoming_eprofile;
            ao2_cleanup(config_eprofile);
            config_eprofile = NULL;
        } else {
            final_eprofile = config_eprofile;
        }
        break;
    case AST_GEOLOC_PRECED_DISCARD_CONFIG:
        final_eprofile = incoming_eprofile;
        ao2_cleanup(config_eprofile);
        config_eprofile = NULL;
        break;
    case AST_GEOLOC_PRECED_PREFER_CONFIG:
        if (config_eprofile) {
            final_eprofile = config_eprofile;
            ao2_cleanup(incoming_eprofile);
            incoming_eprofile = NULL;
        } else {
            final_eprofile = incoming_eprofile;
        }
        break;
    }
 
    if (!final_eprofile) {
        SCOPE_EXIT_RTN("%s: No eprofiles to send.  Done.\n",
            session_name);
    }
 
    if (!final_eprofile->effective_location) {
        ast_geoloc_eprofile_refresh_location(final_eprofile);
    }
 
    buf = ast_str_create(1024);
    if (!buf) {
        SCOPE_EXIT_LOG_RTN(LOG_WARNING, "%s: Unable to allocate buf\n", session_name);
    }
 
    if (final_eprofile->format == AST_GEOLOC_FORMAT_URI) {
        uri = ast_geoloc_eprofile_to_uri(final_eprofile, channel, &buf, session_name);
        if (!uri) {
            SCOPE_EXIT_LOG_RTN(LOG_ERROR, "%s: Unable to create URI from eprofile '%s'\n",
                session_name, final_eprofile->id);
        }
    } else {
        orig_body = tdata->msg->body;
        uri = add_eprofile_to_tdata(final_eprofile, channel, tdata, &buf, session_name);
        if (!uri) {
            tdata->msg->body = orig_body;
            SCOPE_EXIT_LOG_RTN(LOG_ERROR, "%s: Unable to add eprofile '%s' to tdata\n",
                session_name, final_eprofile->id);
        }
    }
 
    uri = ast_strdupa(ast_str_buffer(buf));
    ast_str_reset(buf);
    ast_str_set(&buf, 0, "<%s>", uri);
    if (!ast_strlen_zero(final_eprofile->location_source)) {
        ast_str_append(&buf, 0, ";loc-src=%s", final_eprofile->location_source);
    }
    uri = ast_strdupa(ast_str_buffer(buf));
    ast_trace(4, "%s: Using URI '%s'\n", session_name, uri);
 
 
    /* It's almost impossible for add header to fail but you never know */
    geoloc_hdr = ast_sip_add_header2(tdata, "Geolocation", uri);
    if (geoloc_hdr == NULL) {
        if (orig_body) {
            tdata->msg->body = orig_body;
        }
        SCOPE_EXIT_LOG_RTN(LOG_ERROR, "%s: Unable to add Geolocation header\n", session_name);
    }
    rc = ast_sip_add_header(tdata, "Geolocation-Routing", final_eprofile->allow_routing_use ? "yes" : "no");
    if (rc != 0) {
        if (orig_body) {
            tdata->msg->body = orig_body;
        }
        pj_list_erase(geoloc_hdr);
        SCOPE_EXIT_LOG_RTN(LOG_ERROR, "%s: Unable to add Geolocation-Routing header\n", session_name);
    }
    SCOPE_EXIT_RTN("%s: Geolocation: %s\n", session_name, uri);
}
 
static struct ast_sip_session_supplement geolocation_supplement = {
    .method = "INVITE",
    .priority = AST_SIP_SUPPLEMENT_PRIORITY_CHANNEL + 10,
    .incoming_request = handle_incoming_request,
    .outgoing_request = handle_outgoing_request,
};
 
static int reload_module(void)
{
    return 0;
}
 
static int unload_module(void)
{
    int res = 0;
    ast_sip_session_unregister_supplement(&geolocation_supplement);
 
    return res;
}
 
static int load_module(void)
{
    int res = 0;
    GEOLOCATION_HDR = pj_str("Geolocation");
    GEOLOCATION_ROUTING_HDR = pj_str("Geolocation-Routing");
 
    ast_sip_session_register_supplement(&geolocation_supplement);
 
    return res;
}
 
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "res_pjsip_geolocation Module for Asterisk",
    .support_level = AST_MODULE_SUPPORT_CORE,
    .load = load_module,
    .unload = unload_module,
    .reload = reload_module,
    .load_pri = AST_MODPRI_CHANNEL_DEPEND - 1,
    .requires = "res_geolocation,res_pjsip,res_pjsip_session,chan_pjsip",
);