streams/Code/Nomad/NomadHandler.php

<?php

namespace Code\Nomad;

use Code\Lib\Libzot;

class NomadHandler implements IHandler
{

    public function Notify($data, $hub)
    {
        return self::reply_notify($data, $hub);
    }

    public function Rekey($sender, $data, $hub)
    {
        return self::reply_rekey_request($sender, $data, $hub);
    }

    public function Refresh($sender, $recipients, $hub, $force)
    {
        return self::reply_refresh($sender, $recipients, $hub, $force);
    }

    public function Purge($sender, $recipients, $hub)
    {
        return self::reply_purge($sender, $recipients, $hub);
    }


    // Implementation of specific methods follows;
    // These generally do a small amout of validation and call Libzot
    // to do any heavy lifting

    public static function reply_notify($data, $hub)
    {

        $ret = ['success' => false];

        logger('notify received from ' . $hub['hubloc_url']);

        $x = Libzot::import($data, $hub);
        $ret['delivery_report'] = $x;


        $ret['success'] = true;
        return $ret;
    }


    /**
     * @brief Remote channel info (such as permissions or photo or something)
     * has been updated. Grab a fresh copy and sync it.
     *
     * The difference between refresh and force_refresh is that force_refresh
     * unconditionally creates a directory update record, even if no changes were
     * detected upon processing.
     *
     * @param array $sender
     * @param array $recipients
     *
     * @return array
     */

    public static function reply_refresh($sender, $recipients, $hub, $force)
    {
        $ret = array('success' => false);

        if ($recipients) {
            // This would be a permissions update, typically for one connection

            foreach ($recipients as $recip) {
                $r = q(
                    "select channel.*,xchan.* from channel
					left join xchan on channel_hash = xchan_hash
					where channel_hash ='%s' limit 1",
                    dbesc($recip)
                );

                $x = Libzot::refresh(['hubloc_id_url' => $hub['hubloc_id_url']], $r[0], $force);
            }
        } else {
            // system wide refresh
            $x = Libzot::refresh(['hubloc_id_url' => $hub['hubloc_id_url']], null, $force);
        }

        $ret['success'] = true;
        return $ret;
    }


    public static function reply_rekey_request($sender, $data, $hub)
    {

        $ret = array('success' => false);

        //  newsig is newkey signed with oldkey

        // The original xchan will remain. In Nomad/Receiver we will have imported the new xchan and hubloc to verify
        // the packet authenticity. What we will do now is verify that the keychange operation was signed by the
        // oldkey, and if so change all the abook, abconfig, group, and permission elements which reference the
        // old xchan_hash.

        if ((!$data['old_key']) && (!$data['new_key']) && (!$data['new_sig'])) {
            return $ret;
        }


        $old = null;

        if (Libzot::verify($data['old_guid'], $data['old_guid_sig'], $data['old_key'])) {
            $oldhash = Libzot::make_xchan_hash($data['old_guid'], $data['old_key']);
            $old = q(
                "select * from xchan where xchan_hash = '%s' limit 1",
                dbesc($oldhash)
            );
        } else {
            return $ret;
        }


        if (!$old) {
            return $ret;
        }

        $xchan = $old[0];

        if (!Libzot::verify($data['new_key'], $data['new_sig'], $xchan['xchan_pubkey'])) {
            return $ret;
        }

        $r = q(
            "select * from xchan where xchan_hash = '%s' limit 1",
            dbesc($sender)
        );

        $newxchan = $r[0];

        // @todo
        // if ! $update create a linked identity


        xchan_change_key($xchan, $newxchan, $data);

        $ret['success'] = true;
        return $ret;
    }


    /**
     * @brief
     *
     * @param string $sender
     * @param array $recipients
     *
     * return json_return_and_die()
     */

    public static function reply_purge($sender, $recipients, $hub)
    {

        $ret = array('success' => false);

        if (!$sender) {
            return $ret;
        }

        if ($recipients) {
            // basically this means "unfriend"
            foreach ($recipients as $recip) {
                $channel = q(
                    "select channel.*,xchan.* from channel
					left join xchan on channel_hash = xchan_hash
					where channel_hash = '%s' limit 1",
                    dbesc($recip)
                );
                if ($channel) {
                    $abook = q(
                        "select abook_id from abook where abook_channel = %d and abook_xchan = '%s' limit 1",
                        intval($channel[0]['channel_id']),
                        dbesc($sender)
                    );
                    if ($abook) {
                        contact_remove($channel[0]['channel_id'], $abook[0]['abook_id']);
                    }
                }
            }
            $ret['success'] = true;
        } else {
            // Unfriend everybody - basically this means the channel has committed suicide

            remove_all_xchan_resources($sender);

            $ret['success'] = true;
        }

        return $ret;
    }
}