+ // called directly from dfrn_request due to automatic friend acceptance
+ // any $_POST parameters we may require are supplied in the $handsfree array
+
+ $node = $handsfree['node'];
+ $a->interactive = false; // notice() becomes a no-op since nobody is there to see it
+
+ }
+ else {
+ if($a->argc > 1)
+ $node = $a->argv[1];
+ }
+
+ // Main entry point. Our user received a friend request notification (perhaps
+ // from another site) and clicked 'Approve'. $POST['source_url'] is not set.
+ // OR we have been called directly from dfrn_request ($handsfree != null) due to
+ // this being a page type which supports automatic friend acceptance.
+
+ if(! x($_POST,'source_url')) {
+
+ $uid = ((is_array($handsfree)) ? $handsfree['uid'] : local_user());
+
+ if(! $uid) {
+ notice( t('Permission denied.') . EOL );
+ return;
+ }
+
+ $user = q("SELECT * FROM `user` WHERE `uid` = %d LIMIT 1",
+ intval($uid)
+ );
+
+ if(! $user) {
+ notice( t('Profile not found.') . EOL );
+ return;
+ }
+
+
+ // These come from either the friend request notification form or $handsfree array.
+
+ if(is_array($handsfree)) {
+ $dfrn_id = $handsfree['dfrn_id'];
+ $intro_id = $handsfree['intro_id'];
+ $duplex = $handsfree['duplex'];
+ }
+ else {
+ $dfrn_id = ((x($_POST,'dfrn_id')) ? notags(trim($_POST['dfrn_id'])) : "");
+ $intro_id = intval($_POST['intro_id']);
+ $duplex = intval($_POST['duplex']);
+ $cid = intval($_POST['contact_id']);
+ }
+
+ // The other person will have been issued an ID when they first requested friendship.
+ // Locate their record. At this time, their record will have both pending and blocked set to 1.
+ // There won't be any dfrn_id if this is a network follower, so use the contact_id instead.
+
+ $r = q("SELECT * FROM `contact` WHERE ( ( `issued-id` != '' AND `issued-id` = '%s' ) OR ( `id` = %d AND `id` != 0 ) ) AND `uid` = %d LIMIT 1",
+ dbesc($dfrn_id),
+ intval($cid),
+ intval($uid)
+ );
+
+ if(! count($r)) {
+ notice( t('Contact not found.') . EOL );
+ return;
+ }
+
+ $contact = $r[0];
+
+ $contact_id = $contact['id'];
+ $relation = $contact['rel'];
+ $site_pubkey = $contact['site-pubkey'];
+ $dfrn_confirm = $contact['confirm'];
+ $aes_allow = $contact['aes_allow'];
+
+
+ if($contact['network'] === 'dfrn') {
+
+ // Generate a key pair for all further communications with this person.
+ // We have a keypair for every contact, and a site key for unknown people.
+ // This provides a means to carry on relationships with other people if
+ // any single key is compromised. It is a robust key. We're much more
+ // worried about key leakage than anybody cracking it.
+
+ $res = openssl_pkey_new(array(
+ 'digest_alg' => 'whirlpool',
+ 'private_key_bits' => 4096,
+ 'encrypt_key' => false )
+ );
+
+
+ $private_key = '';
+
+ openssl_pkey_export($res, $private_key);
+
+ $pubkey = openssl_pkey_get_details($res);
+ $public_key = $pubkey["key"];
+
+ // Save the private key. Send them the public key.
+
+ $r = q("UPDATE `contact` SET `prvkey` = '%s' WHERE `id` = %d AND `uid` = %d LIMIT 1",
+ dbesc($private_key),
+ intval($contact_id),
+ intval($uid)
+ );
+
+ $params = array();
+
+ // Per the protocol document, we will verify both ends by encrypting the dfrn_id with our
+ // site private key (person on the other end can decrypt it with our site public key).
+ // Then encrypt our profile URL with the other person's site public key. They can decrypt
+ // it with their site private key. If the decryption on the other end fails for either
+ // item, it indicates tampering or key failure on at least one site and we will not be
+ // able to provide a secure communication pathway.
+
+ // If other site is willing to accept full encryption, (aes_allow is 1 AND we have php5.3
+ // or later) then we encrypt the personal public key we send them using AES-256-CBC and a
+ // random key which is encrypted with their site public key.
+
+ $src_aes_key = random_string();
+
+ $result = '';
+ openssl_private_encrypt($dfrn_id,$result,$user[0]['prvkey']);
+
+ $params['dfrn_id'] = bin2hex($result);
+ $params['public_key'] = $public_key;
+
+
+ $my_url = $a->get_baseurl() . '/profile/' . $user[0]['nickname'];
+
+ openssl_public_encrypt($my_url, $params['source_url'], $site_pubkey);
+ $params['source_url'] = bin2hex($params['source_url']);
+
+ if($aes_allow && function_exists('openssl_encrypt')) {
+ openssl_public_encrypt($src_aes_key, $params['aes_key'], $site_pubkey);
+ $params['aes_key'] = bin2hex($params['aes_key']);
+ $params['public_key'] = bin2hex(openssl_encrypt($public_key,'AES-256-CBC',$src_aes_key));
+ }
+
+ $params['dfrn_version'] = DFRN_PROTOCOL_VERSION ;
+ if($duplex == 1)
+ $params['duplex'] = 1;
+
+ // POST all this stuff to the other site.
+
+ $res = post_url($dfrn_confirm,$params);
+
+ // Now figure out what they responded. Try to be robust if the remote site is
+ // having difficulty and throwing up errors of some kind.
+
+ $leading_junk = substr($res,0,strpos($res,'<?xml'));
+
+ $res = substr($res,strpos($res,'<?xml'));
+ if(! strlen($res)) {
+
+ // No XML at all, this exchange is messed up really bad.
+ // We shouldn't proceed, because the xml parser might choke,
+ // and $status is going to be zero, which indicates success.
+ // We can hardly call this a success.
+
+ notice( t('Response from remote site was not understood.') . EOL);
+ return;
+ }
+
+ if(strlen($leading_junk) && get_config('system','debugging')) {
+
+ // This might be more common. Mixed error text and some XML.
+ // If we're configured for debugging, show the text. Proceed in either case.
+
+ notice( t('Unexpected response from remote site: ') . EOL . $leading_junk . EOL );
+ }
+
+ $xml = simplexml_load_string($res);
+ $status = (int) $xml->status;
+ $message = unxmlify($xml->message); // human readable text of what may have gone wrong.
+ switch($status) {
+ case 0:
+ notice( t("Confirmation completed successfully.") . EOL);
+ if(strlen($message))
+ notice( t('Remote site reported: ') . $message . EOL);
+ break;
+ case 1:
+ // birthday paradox - generate new dfrn-id and fall through.
+ $new_dfrn_id = random_string();
+ $r = q("UPDATE contact SET `issued-id` = '%s' WHERE `id` = %d AND `uid` = %d LIMIT 1",
+ dbesc($new_dfrn_id),
+ intval($contact_id),
+ intval($uid)
+ );
+
+ case 2:
+ notice( t("Temporary failure. Please wait and try again.") . EOL);
+ if(strlen($message))
+ notice( t('Remote site reported: ') . $message . EOL);
+ break;
+
+
+ case 3:
+ notice( t("Introduction failed or was revoked.") . EOL);
+ if(strlen($message))
+ notice( t('Remote site reported: ') . $message . EOL);
+ break;
+ }
+
+ if(($status == 0) && ($intro_id)) {
+
+ // Success. Delete the notification.
+
+ $r = q("DELETE FROM `intro` WHERE `id` = %d AND `uid` = %d LIMIT 1",
+ intval($intro_id),
+ intval($uid)
+ );
+
+ }
+
+ if($status != 0)
+ return;
+ }
+
+ // We have now established a relationship with the other site.
+ // Let's make our own personal copy of their profile photo so we don't have
+ // to always load it from their site.
+
+ require_once("Photo.php");
+
+ $photos = import_profile_photo($contact['photo'],$uid,$contact_id);
+
+ if($contact['network'] === 'dfrn') {
+
+ $new_relation = REL_VIP;
+ if(($relation == REL_FAN) || ($duplex))
+ $new_relation = REL_BUD;
+
+ $r = q("UPDATE `contact` SET `photo` = '%s',
+ `thumb` = '%s',
+ `rel` = %d,
+ `name-date` = '%s',
+ `uri-date` = '%s',
+ `avatar-date` = '%s',
+ `blocked` = 0,
+ `pending` = 0,
+ `duplex` = %d,
+ `network` = 'dfrn' WHERE `id` = %d LIMIT 1
+ ",
+ dbesc($photos[0]),
+ dbesc($photos[1]),
+ intval($new_relation),
+ dbesc(datetime_convert()),
+ dbesc(datetime_convert()),
+ dbesc(datetime_convert()),
+ intval($duplex),
+ intval($contact_id)
+ );
+ }
+ else {
+
+ $notify = '';
+ $poll = '';
+
+ // $contact['network'] !== 'dfrn'
+
+ $arr = lrdd($contact['url']);
+ if(count($arr)) {
+ foreach($arr as $link) {
+ if($link['@attributes']['rel'] === 'salmon')
+ $notify = $link['@attributes']['href'];
+ if($link['@attributes']['rel'] === NAMESPACE_FEED)
+ $poll = $link['@attributes']['href'];
+ }
+ }
+
+ $r = q("DELETE FROM `intro` WHERE `id` = %d AND `uid` = %d LIMIT 1",
+ intval($intro_id),
+ intval($uid)
+ );
+
+ $r = q("UPDATE `contact` SET `photo` = '%s',
+ `thumb` = '%s',
+ `name-date` = '%s',
+ `uri-date` = '%s',
+ `avatar-date` = '%s',
+ `notify` = '%s',
+ `poll` = '%s',
+ `blocked` = 0,
+ `pending` = 0
+ WHERE `id` = %d LIMIT 1
+ ",
+ dbesc($photos[0]),
+ dbesc($photos[1]),
+ dbesc(datetime_convert()),
+ dbesc(datetime_convert()),
+ dbesc(datetime_convert()),
+ dbesc($notify),
+ dbesc($poll),
+ intval($contact_id)
+ );
+ }
+
+ if($r === false)
+ notice( t('Unable to set contact photo.') . EOL);
+
+
+ // Let's send our user to the contact editor in case they want to
+ // do anything special with this new friend.
+
+ if($handsfree === null)
+ goaway($a->get_baseurl() . '/contacts/' . intval($contact_id));
+ return; //NOTREACHED
+
+ }
+
+
+
+ // End of first scenario. [Local confirmation of remote friend request].
+
+
+
+ // Begin scenario two. This is the remote response to the above scenario.
+ // This will take place on the site that originally initiated the friend request.
+ // In the section above where the confirming party makes a POST and
+ // retrieves xml status information, they are communicating with the following code.