+ }
+ else {
+ if($a->argc > 1)
+ $node = $a->argv[1];
+ }
+
+ /**
+ *
+ * Main entry point. Scenario 1. Our user received a friend request notification (perhaps
+ * from another site) and clicked 'Approve'.
+ * $POST['source_url'] is not set. If it is, it indicates Scenario 2.
+ *
+ * We may also have been called directly from dfrn_request ($handsfree != null) due to
+ * this being a page type which supports automatic friend acceptance. That is also Scenario 1
+ * since we are operating on behalf of our registered user to approve a friendship.
+ *
+ */
+
+ 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 data elements may come from either the friend request notification form or $handsfree array.
+
+ if(is_array($handsfree)) {
+ logger('dfrn_confirm: Confirm in handsfree mode');
+ $dfrn_id = $handsfree['dfrn_id'];
+ $intro_id = $handsfree['intro_id'];
+ $duplex = $handsfree['duplex'];
+ $hidden = ((array_key_exists('hidden',$handsfree)) ? intval($handsfree['hidden']) : 0 );
+ }
+ else {
+ $dfrn_id = ((x($_POST,'dfrn_id')) ? notags(trim($_POST['dfrn_id'])) : "");
+ $intro_id = ((x($_POST,'intro_id')) ? intval($_POST['intro_id']) : 0 );
+ $duplex = ((x($_POST,'duplex')) ? intval($_POST['duplex']) : 0 );
+ $cid = ((x($_POST,'contact_id')) ? intval($_POST['contact_id']) : 0 );
+ $hidden = ((x($_POST,'hidden')) ? intval($_POST['hidden']) : 0 );
+ }
+
+ /**
+ *
+ * Ensure that dfrn_id has precedence when we go to find the contact record.
+ * We only want to search based on contact id if there is no dfrn_id,
+ * e.g. for OStatus network followers.
+ *
+ */
+
+ if(strlen($dfrn_id))
+ $cid = 0;
+
+ logger('dfrn_confirm: Confirming request for dfrn_id (issued) ' . $dfrn_id);
+ if($cid)
+ logger('dfrn_confirm: Confirming follower with contact_id: ' . $cid);
+
+
+ /**
+ *
+ * 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)) {
+ logger('dfrn_confirm: Contact not found in DB.');
+ 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'];
+
+ $network = ((strlen($contact['issued-id'])) ? NETWORK_DFRN : NETWORK_OSTATUS);
+
+ if($contact['network'])
+ $network = $contact['network'];
+
+ if($network === 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' => 'sha1',
+ '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 DFRN protocol, 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;
+
+ logger('dfrn_confirm: Confirm: posting data to ' . $dfrn_confirm . ': ' . print_r($params,true), LOGGER_DATA);
+
+ /**
+ *
+ * POST all this stuff to the other site.
+ * Temporarily raise the network timeout to 120 seconds because the default 60
+ * doesn't always give the other side quite enough time to decrypt everything.
+ *
+ */
+
+ $a->config['system']['curl_timeout'] = 120;
+
+ $res = post_url($dfrn_confirm,$params);
+
+ logger('dfrn_confirm: Confirm: received data: ' . $res, LOGGER_DATA);
+
+ // 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.