]> git.mxchange.org Git - friendica.git/blobdiff - include/diaspora.php
Small bugfix
[friendica.git] / include / diaspora.php
index 14ff6e42f8931c67ce997d647a400d76f2c89026..18206be8ed88bae758a1cf83a694bdc125851ff8 100644 (file)
@@ -2,41 +2,6 @@
 /**
  * @file include/diaspora.php
  * @brief The implementation of the diaspora protocol
- *
- * Checklist:
- *
- * Checked:
- * - send status
- * - send comment
- * - send like
- * - send mail
- * - send status retraction
- * - send comment retraction on own post
- * - send like retraction on own post
- * - send comment retraction on diaspora post
- * - send like retraction on diaspora post
- * - receive status
- * - receive reshare
- * - receive comment
- * - receive like
- * - receive connect request
- * - receive profile data
- * - receive mail
- * - receive comment retraction
- * - receive like retraction
- * - relay comment
- * - relay like
- * - relay comment retraction from diaspora
- * - relay comment retraction from friendica
- * - relay like retraction from diaspora
- * - relay like retraction from friendica
- * - send share
- *
- * Should work:
- * - receive account deletion
- * - send unshare
- *
- * Unchecked:
  */
 
 require_once("include/items.php");
@@ -110,13 +75,15 @@ class diaspora {
        /**
         * @brief repairs a signature that was double encoded
         *
+        * The function is unused at the moment. It was copied from the old implementation.
+        *
         * @param string $signature The signature
         * @param string $handle The handle of the signature owner
         * @param integer $level This value is only set inside this function to avoid endless loops
         *
-        * @return the repaired signature
+        * @return string the repaired signature
         */
-       function repair_signature($signature, $handle = "", $level = 1) {
+       private function repair_signature($signature, $handle = "", $level = 1) {
 
                if ($signature == "")
                        return ($signature);
@@ -144,7 +111,7 @@ class diaspora {
         * 'author' -> author diaspora handle
         * 'key' -> author public key (converted to pkcs#8)
         */
-       function decode($importer, $xml) {
+       public static function decode($importer, $xml) {
 
                $public = false;
                $basedom = parse_xml_string($xml);
@@ -177,16 +144,6 @@ class diaspora {
 
                        $decrypted = pkcs5_unpad($decrypted);
 
-                       /**
-                        * $decrypted now contains something like
-                        *
-                        *  <decrypted_header>
-                        *     <iv>8e+G2+ET8l5BPuW0sVTnQw==</iv>
-                        *     <aes_key>UvSMb4puPeB14STkcDWq+4QE302Edu15oaprAQSkLKU=</aes_key>
-                        *     <author_id>galaxor@diaspora.priateship.org</author_id>
-                        *  </decrypted_header>
-                        */
-
                        logger('decrypted: '.$decrypted, LOGGER_DEBUG);
                        $idom = parse_xml_string($decrypted,false);
 
@@ -285,7 +242,7 @@ class diaspora {
         *
         * @param array $msg The post that will be dispatched
         *
-        * @return bool Was the message accepted?
+        * @return int The message id of the generated message, "true" or "false" if there was an error
         */
        public static function dispatch_public($msg) {
 
@@ -297,7 +254,7 @@ class diaspora {
 
                // Use a dummy importer to import the data for the public copy
                $importer = array("uid" => 0, "page-flags" => PAGE_FREELOVE);
-               $item_id = self::dispatch($importer,$msg);
+               $message_id = self::dispatch($importer,$msg);
 
                // Now distribute it to the followers
                $r = q("SELECT `user`.* FROM `user` WHERE `user`.`uid` IN
@@ -314,7 +271,7 @@ class diaspora {
                } else
                        logger("No subscribers for ".$msg["author"]." ".print_r($msg, true));
 
-               return $item_id;
+               return $message_id;
        }
 
        /**
@@ -323,7 +280,7 @@ class diaspora {
         * @param array $importer Array of the importer user
         * @param array $msg The post that will be dispatched
         *
-        * @return bool Was the message accepted?
+        * @return int The message id of the generated message, "true" or "false" if there was an error
         */
        public static function dispatch($importer, $msg) {
 
@@ -347,6 +304,9 @@ class diaspora {
                        case "comment":
                                return self::receive_comment($importer, $sender, $fields, $msg["message"]);
 
+                       case "contact":
+                               return self::receive_contact_request($importer, $fields);
+
                        case "conversation":
                                return self::receive_conversation($importer, $msg, $fields);
 
@@ -368,9 +328,6 @@ class diaspora {
                        case "profile":
                                return self::receive_profile($importer, $fields);
 
-                       case "request":
-                               return self::receive_request($importer, $fields);
-
                        case "reshare":
                                return self::receive_reshare($importer, $fields, $msg["message"]);
 
@@ -403,8 +360,10 @@ class diaspora {
 
                $data = parse_xml_string($msg["message"], false);
 
-               if (!is_object($data))
+               if (!is_object($data)) {
+                       logger("No valid XML ".$msg["message"], LOGGER_DEBUG);
                        return false;
+               }
 
                $first_child = $data->getName();
 
@@ -426,6 +385,9 @@ class diaspora {
                if (in_array($type, array("signed_retraction", "relayable_retraction")))
                        $type = "retraction";
 
+               if ($type == "request")
+                       $type = "contact";
+
                $fields = new SimpleXMLElement("<".$type."/>");
 
                $signed_data = "";
@@ -462,11 +424,11 @@ class diaspora {
                                }
                        }
 
-                       if ($fieldname == "author_signature")
+                       if (($fieldname == "author_signature") AND ($entry != ""))
                                $author_signature = base64_decode($entry);
-                       elseif ($fieldname == "parent_author_signature")
+                       elseif (($fieldname == "parent_author_signature") AND ($entry != ""))
                                $parent_author_signature = base64_decode($entry);
-                       elseif ($fieldname != "target_author_signature") {
+                       elseif (!in_array($fieldname, array("author_signature", "parent_author_signature", "target_author_signature"))) {
                                if ($signed_data != "") {
                                        $signed_data .= ";";
                                        $signed_data_parent .= ";";
@@ -491,19 +453,27 @@ class diaspora {
                        return true;
 
                // No author_signature? This is a must, so we quit.
-               if (!isset($author_signature))
+               if (!isset($author_signature)) {
+                       logger("No author signature for type ".$type." - Message: ".$msg["message"], LOGGER_DEBUG);
                        return false;
+               }
 
                if (isset($parent_author_signature)) {
                        $key = self::key($msg["author"]);
 
-                       if (!rsa_verify($signed_data, $parent_author_signature, $key, "sha256"))
+                       if (!rsa_verify($signed_data, $parent_author_signature, $key, "sha256")) {
+                               logger("No valid parent author signature for author ".$msg["author"]. " in type ".$type." - signed data: ".$signed_data." - Message: ".$msg["message"]." - Signature ".$parent_author_signature, LOGGER_DEBUG);
                                return false;
+                       }
                }
 
                $key = self::key($fields->author);
 
-               return rsa_verify($signed_data, $author_signature, $key, "sha256");
+               if (!rsa_verify($signed_data, $author_signature, $key, "sha256")) {
+                       logger("No valid author signature for author ".$msg["author"]. " in type ".$type." - signed data: ".$signed_data." - Message: ".$msg["message"]." - Signature ".$author_signature, LOGGER_DEBUG);
+                       return false;
+               } else
+                       return true;
        }
 
        /**
@@ -655,7 +625,7 @@ class diaspora {
 
                        if($contact['addr'] != "")
                                $handle = $contact['addr'];
-                       elseif(($contact['network'] === NETWORK_DFRN) || ($contact['self'] == 1)) {
+                       else {
                                $baseurl_start = strpos($contact['url'],'://') + 3;
                                $baseurl_length = strpos($contact['url'],'/profile') - $baseurl_start; // allows installations in a subdirectory--not sure how Diaspora will handle
                                $baseurl = substr($contact['url'], $baseurl_start, $baseurl_length);
@@ -742,7 +712,7 @@ class diaspora {
         * @param string $handle The checked handle in the format user@domain.tld
         * @param bool $is_comment Is the check for a comment?
         *
-        * @return bool is posting allowed?
+        * @return array The contact data
         */
        private function allowed_contact_by_handle($importer, $handle, $is_comment = false) {
                $contact = self::contact_by_handle($importer["uid"], $handle);
@@ -764,7 +734,7 @@ class diaspora {
         * @param int $uid The user id
         * @param string $guid The guid of the message
         *
-        * @return bool "true" if the message already was stored into the system
+        * @return int|bool message id if the message already was stored into the system - or false.
         */
        private function message_exists($uid, $guid) {
                $r = q("SELECT `id` FROM `item` WHERE `uid` = %d AND `guid` = '%s' LIMIT 1",
@@ -774,7 +744,7 @@ class diaspora {
 
                if($r) {
                        logger("message ".$guid." already exists for user ".$uid);
-                       return true;
+                       return $r[0]["id"];
                }
 
                return false;
@@ -793,7 +763,7 @@ class diaspora {
        }
 
        /**
-        * @brief sub function of "fetch_guid"
+        * @brief sub function of "fetch_guid" which checks for links in messages
         *
         * @param array $match array containing a link that has to be checked for a message link
         * @param array $item The item array
@@ -836,7 +806,10 @@ class diaspora {
         * @param string $server The url of the server
         * @param int $level Endless loop prevention
         *
-        * @return array of message, author and public key
+        * @return array
+        *      'message' => The message XML
+        *      'author' => The author handle
+        *      'key' => The public key of the author
         */
        private function message($guid, $server, $level = 0) {
 
@@ -887,7 +860,7 @@ class diaspora {
         * @param int $uid The user id
         * @param string $guid message guid
         * @param string $author The handle of the item
-        * @param array $contact The contact that is checked
+        * @param array $contact The contact of the item owner
         *
         * @return array the item record
         */
@@ -933,7 +906,9 @@ class diaspora {
         * @param array $person The record of the person
         * @param int $uid The user id
         *
-        * @return array of contact id and network type
+        * @return array
+        *      'cid' => contact id
+        *      'network' => network type
         */
        private function author_contact_by_url($contact, $person, $uid) {
 
@@ -992,14 +967,17 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes an account deletion
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         *
-        * @return 
+        * @return bool Success
         */
        private function receive_account_deletion($importer, $data) {
+
+               /// @todo Account deletion should remove the contact from the global contacts as well
+
                $author = notags(unxmlify($data->author));
 
                $contact = self::contact_by_handle($importer["uid"], $author);
@@ -1014,7 +992,24 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Fetch the uri from our database if we already have this item (maybe from ourselves)
+        *
+        * @param string $author Author handle
+        * @param string $guid Message guid
+        *
+        * @return string The constructed uri or the one from our database
+        */
+       private function get_uri_from_guid($author, $guid) {
+
+               $r = q("SELECT `uri` FROM `item` WHERE `guid` = '%s' LIMIT 1", dbesc($guid));
+               if ($r)
+                       return $r[0]["uri"];
+               else
+                       return $author.":".$guid;
+       }
+
+       /**
+        * @brief Processes an incoming comment
         *
         * @param array $importer Array of the importer user
         * @param string $sender The sender of the message
@@ -1033,8 +1028,9 @@ class diaspora {
                if (!$contact)
                        return false;
 
-               if (self::message_exists($importer["uid"], $guid))
-                       return false;
+               $message_id = self::message_exists($importer["uid"], $guid);
+               if ($message_id)
+                       return $message_id;
 
                $parent_item = self::parent_item($importer["uid"], $parent_guid, $author, $contact);
                if (!$parent_item)
@@ -1064,7 +1060,7 @@ class diaspora {
                $datarray["owner-avatar"] = ((x($contact,"thumb")) ? $contact["thumb"] : $contact["photo"]);
 
                $datarray["guid"] = $guid;
-               $datarray["uri"] = $author.":".$guid;
+               $datarray["uri"] = self::get_uri_from_guid($author, $guid);
 
                $datarray["type"] = "remote-comment";
                $datarray["verb"] = ACTIVITY_POST;
@@ -1104,7 +1100,7 @@ class diaspora {
         * @brief processes and stores private messages
         *
         * @param array $importer Array of the importer user
-        * @param array $contact The contact that is checked
+        * @param array $contact The contact of the message
         * @param object $data The message object
         * @param array $msg Array of the processed message, author handle and key
         * @param object $mesg The private message
@@ -1230,13 +1226,13 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes new private messages (answers to private messages are processed elsewhere)
         *
         * @param array $importer Array of the importer user
         * @param array $msg Array of the processed message, author handle and key
         * @param object $data The message object
         *
-        * @return 
+        * @return bool Success
         */
        private function receive_conversation($importer, $msg, $data) {
                $guid = notags(unxmlify($data->guid));
@@ -1296,13 +1292,13 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Creates the body for a "like" message
         *
-        * @param array $contact The contact that is checked
-        * @param $parent_item
+        * @param array $contact The contact that send us the "like"
+        * @param array $parent_item The item array of the parent item
         * @param string $guid message guid
         *
-        * @return 
+        * @return string the body
         */
        private function construct_like_body($contact, $parent_item, $guid) {
                $bodyverb = t('%1$s likes %2$s\'s %3$s');
@@ -1315,12 +1311,12 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Creates a XML object for a "like"
         *
         * @param array $importer Array of the importer user
-        * @param $parent_item
+        * @param array $parent_item The item array of the parent item
         *
-        * @return 
+        * @return string The XML
         */
        private function construct_like_object($importer, $parent_item) {
                $objtype = ACTIVITY_OBJ_NOTE;
@@ -1338,7 +1334,7 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes "like" messages
         *
         * @param array $importer Array of the importer user
         * @param string $sender The sender of the message
@@ -1362,8 +1358,9 @@ class diaspora {
                if (!$contact)
                        return false;
 
-               if (self::message_exists($importer["uid"], $guid))
-                       return false;
+               $message_id = self::message_exists($importer["uid"], $guid);
+               if ($message_id)
+                       return $message_id;
 
                $parent_item = self::parent_item($importer["uid"], $parent_guid, $author, $contact);
                if (!$parent_item)
@@ -1380,7 +1377,7 @@ class diaspora {
 
                // "positive" = "false" would be a Dislike - wich isn't currently supported by Diaspora
                // We would accept this anyhow.
-               if ($positive === "true")
+               if ($positive == "true")
                        $verb = ACTIVITY_LIKE;
                else
                        $verb = ACTIVITY_DISLIKE;
@@ -1400,7 +1397,7 @@ class diaspora {
                $datarray["owner-avatar"] = ((x($contact,"thumb")) ? $contact["thumb"] : $contact["photo"]);
 
                $datarray["guid"] = $guid;
-               $datarray["uri"] = $author.":".$guid;
+               $datarray["uri"] = self::get_uri_from_guid($author, $guid);
 
                $datarray["type"] = "activity";
                $datarray["verb"] = $verb;
@@ -1435,12 +1432,12 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes private messages
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         *
-        * @return 
+        * @return bool Success?
         */
        private function receive_message($importer, $data) {
                $guid = notags(unxmlify($data->guid));
@@ -1514,7 +1511,7 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes participations - unsupported by now
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
@@ -1527,12 +1524,12 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes photos - unneeded
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         *
-        * @return 
+        * @return bool always true
         */
        private function receive_photo($importer, $data) {
                // There doesn't seem to be a reason for this function, since the photo data is transmitted in the status message as well
@@ -1540,12 +1537,12 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes poll participations - unssupported
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         *
-        * @return 
+        * @return bool always true
         */
        private function receive_poll_participation($importer, $data) {
                // We don't support polls by now
@@ -1553,12 +1550,12 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes incoming profile updates
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         *
-        * @return 
+        * @return bool Success
         */
        private function receive_profile($importer, $data) {
                $author = notags(unxmlify($data->author));
@@ -1646,12 +1643,10 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes incoming friend requests
         *
         * @param array $importer Array of the importer user
-        * @param array $contact The contact that is checked
-        *
-        * @return 
+        * @param array $contact The contact that send the request
         */
        private function receive_request_make_friend($importer, $contact) {
 
@@ -1699,11 +1694,8 @@ class diaspora {
                                $BPhoto = "[url=".$contact["url"]."][img]".$contact["thumb"]."[/img][/url]";
                                $arr["body"] = sprintf(t("%1$s is now friends with %2$s"), $A, $B)."\n\n\n".$Bphoto;
 
-                               $arr["object"] = "<object><type>".ACTIVITY_OBJ_PERSON."</type><title>".$contact["name"]."</title>"
-                                       ."<id>".$contact["url"]."/".$contact["name"]."</id>";
-                               $arr["object"] .= "<link>".xmlify('<link rel="alternate" type="text/html" href="'.$contact["url"].'" />'."\n");
-                               $arr["object"] .= xmlify('<link rel="photo" type="image/jpeg" href="'.$contact["thumb"].'" />'."\n");
-                               $arr["object"] .= "</link></object>\n";
+                               $arr["object"] = self::construct_new_friend_object($contact);
+
                                $arr["last-child"] = 1;
 
                                $arr["allow_cid"] = $user[0]["allow_cid"];
@@ -1714,36 +1706,75 @@ class diaspora {
                                $i = item_store($arr);
                                if($i)
                                        proc_run("php", "include/notifier.php", "activity", $i);
-
                        }
-
                }
        }
 
        /**
-        * @brief 
+        * @brief Creates a XML object for a "new friend" message
+        *
+        * @param array $contact Array of the contact
+        *
+        * @return string The XML
+        */
+        private function construct_new_friend_object($contact) {
+                $objtype = ACTIVITY_OBJ_PERSON;
+                $link = '<link rel="alternate" type="text/html" href="'.$contact["url"].'" />'."\n".
+                        '<link rel="photo" type="image/jpeg" href="'.$contact["thumb"].'" />'."\n";
+
+                $xmldata = array("object" => array("type" => $objtype,
+                                                "title" => $contact["name"],
+                                                "id" => $contact["url"]."/".$contact["name"],
+                                                "link" => $link));
+
+                return xml::from_array($xmldata, $xml, true);
+        }
+
+       /**
+        * @brief Processes incoming sharing notification
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         *
-        * @return 
+        * @return bool Success
         */
-       private function receive_request($importer, $data) {
+       private function receive_contact_request($importer, $data) {
                $author = unxmlify($data->author);
                $recipient = unxmlify($data->recipient);
 
                if (!$author || !$recipient)
-                       return;
+                       return false;
 
-               $contact = self::contact_by_handle($importer["uid"],$author);
+               // the current protocol version doesn't know these fields
+               // That means that we will assume their existance
+               if (isset($data->following))
+                       $following = (unxmlify($data->following) == "true");
+               else
+                       $following = true;
 
-               if($contact) {
+               if (isset($data->sharing))
+                       $sharing = (unxmlify($data->sharing) == "true");
+               else
+                       $sharing = true;
 
-                       // perhaps we were already sharing with this person. Now they're sharing with us.
-                       // That makes us friends.
+               $contact = self::contact_by_handle($importer["uid"],$author);
 
-                       self::receive_request_make_friend($importer, $contact);
-                       return true;
+               // perhaps we were already sharing with this person. Now they're sharing with us.
+               // That makes us friends.
+               if ($contact) {
+                       if ($following AND $sharing) {
+                               self::receive_request_make_friend($importer, $contact);
+                               return true;
+                       } else /// @todo Handle all possible variations of adding and retracting of permissions
+                               return false;
+               }
+
+               if (!$following AND $sharing AND in_array($importer["page-flags"], array(PAGE_SOAPBOX, PAGE_NORMAL))) {
+                       logger("Author ".$author." wants to share with us - but doesn't want to listen. Request is ignored.", LOGGER_DEBUG);
+                       return false;
+               } elseif (!$following AND !$sharing) {
+                       logger("Author ".$author." doesn't want anything - and we don't know the author. Request is ignored.", LOGGER_DEBUG);
+                       return false;
                }
 
                $ret = self::person_by_handle($author);
@@ -1783,12 +1814,12 @@ class diaspora {
                        return;
                }
 
-               $g = q("SELECT `def_gid` FROM `user` WHERE `uid` = %d LIMIT 1",
-                       intval($importer["uid"])
-               );
+               $def_gid = get_default_group($importer['uid'], $ret["network"]);
+
+               if(intval($def_gid))
+                       group_add_member($importer["uid"], "", $contact_record["id"], $def_gid);
 
-               if($g && intval($g[0]["def_gid"]))
-                       group_add_member($importer["uid"], "", $contact_record["id"], $g[0]["def_gid"]);
+               update_contact_avatar($ret["photo"], $importer['uid'], $contact_record["id"], true);
 
                if($importer["page-flags"] == PAGE_NORMAL) {
 
@@ -1814,8 +1845,10 @@ class diaspora {
                        // but if our page-type is PAGE_COMMUNITY or PAGE_SOAPBOX
                        // we are going to change the relationship and make them a follower.
 
-                       if($importer["page-flags"] == PAGE_FREELOVE)
+                       if (($importer["page-flags"] == PAGE_FREELOVE) AND $sharing AND $following)
                                $new_relation = CONTACT_IS_FRIEND;
+                       elseif (($importer["page-flags"] == PAGE_FREELOVE) AND $sharing)
+                               $new_relation = CONTACT_IS_SHARING;
                        else
                                $new_relation = CONTACT_IS_FOLLOWER;
 
@@ -1842,13 +1875,13 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Fetches a message with a given guid
         *
         * @param string $guid message guid
-        * @param $orig_author
-        * @param $author
+        * @param string $orig_author handle of the original post
+        * @param string $author handle of the sharer
         *
-        * @return 
+        * @return array The fetched item
         */
        private function original_item($guid, $orig_author, $author) {
 
@@ -1862,10 +1895,18 @@ class diaspora {
                        logger("reshared message ".$guid." already exists on system.");
 
                        // Maybe it is already a reshared item?
-                       // Then refetch the content, since there can be many side effects with reshared posts from other networks or reshares from reshares
-                       if (self::is_reshare($r[0]["body"], false))
+                       // Then refetch the content, if it is a reshare from a reshare.
+                       // If it is a reshared post from another network then reformat to avoid display problems with two share elements
+                       if (self::is_reshare($r[0]["body"], true))
                                $r = array();
-                       else
+                       elseif (self::is_reshare($r[0]["body"], false)) {
+                               $r[0]["body"] = diaspora2bb(bb2diaspora($r[0]["body"]));
+
+                               // Add OEmbed and other information to the body
+                               $r[0]["body"] = add_page_info_to_body($r[0]["body"], false, true);
+
+                               return $r[0];
+                       } else
                                return $r[0];
                }
 
@@ -1898,8 +1939,13 @@ class diaspora {
                                        FROM `item` WHERE `id` = %d AND `visible` AND NOT `deleted` AND `body` != '' LIMIT 1",
                                        intval($item_id));
 
-                               if ($r)
+                               if ($r) {
+                                       // If it is a reshared post from another network then reformat to avoid display problems with two share elements
+                                       if (self::is_reshare($r[0]["body"], false))
+                                               $r[0]["body"] = diaspora2bb(bb2diaspora($r[0]["body"]));
+
                                        return $r[0];
+                               }
 
                        }
                }
@@ -1907,13 +1953,13 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes a reshare message
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         * @param string $xml The original XML of the message
         *
-        * @return 
+        * @return int the message id
         */
        private function receive_reshare($importer, $data, $xml) {
                $root_author = notags(unxmlify($data->root_author));
@@ -1927,8 +1973,9 @@ class diaspora {
                if (!$contact)
                        return false;
 
-               if (self::message_exists($importer["uid"], $guid))
-                       return false;
+               $message_id = self::message_exists($importer["uid"], $guid);
+               if ($message_id)
+                       return $message_id;
 
                $original_item = self::original_item($root_guid, $root_author, $author);
                if (!$original_item)
@@ -1951,7 +1998,7 @@ class diaspora {
                $datarray["owner-avatar"] = $datarray["author-avatar"];
 
                $datarray["guid"] = $guid;
-               $datarray["uri"] = $datarray["parent-uri"] = $author.":".$guid;
+               $datarray["uri"] = $datarray["parent-uri"] = self::get_uri_from_guid($author, $guid);
 
                $datarray["verb"] = ACTIVITY_POST;
                $datarray["gravity"] = GRAVITY_PARENT;
@@ -1981,13 +2028,13 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Processes retractions
         *
         * @param array $importer Array of the importer user
-        * @param array $contact The contact that is checked
+        * @param array $contact The contact of the item owner
         * @param object $data The message object
         *
-        * @return 
+        * @return bool success
         */
        private function item_retraction($importer, $contact, $data) {
                $target_type = notags(unxmlify($data->target_type));
@@ -2038,16 +2085,18 @@ class diaspora {
                        // notify others
                        proc_run("php", "include/notifier.php", "drop", $r[0]["id"]);
                }
+
+               return true;
        }
 
        /**
-        * @brief 
+        * @brief Receives retraction messages
         *
         * @param array $importer Array of the importer user
         * @param string $sender The sender of the message
         * @param object $data The message object
         *
-        * @return 
+        * @return bool Success
         */
        private function receive_retraction($importer, $sender, $data) {
                $target_type = notags(unxmlify($data->target_type));
@@ -2068,10 +2117,11 @@ class diaspora {
                        case "StatusMessage":
                                return self::item_retraction($importer, $contact, $data);;
 
+                       case "Contact":
                        case "Person":
                                /// @todo What should we do with an "unshare"?
                                // Removing the contact isn't correct since we still can read the public items
-                               //contact_remove($contact["id"]);
+                               contact_remove($contact["id"]);
                                return true;
 
                        default:
@@ -2082,13 +2132,13 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Receives status messages
         *
         * @param array $importer Array of the importer user
         * @param object $data The message object
         * @param string $xml The original XML of the message
         *
-        * @return 
+        * @return int The message id of the newly created item
         */
        private function receive_status_message($importer, $data, $xml) {
 
@@ -2109,8 +2159,9 @@ class diaspora {
                if (!$contact)
                        return false;
 
-               if (self::message_exists($importer["uid"], $guid))
-                       return false;
+               $message_id = self::message_exists($importer["uid"], $guid);
+               if ($message_id)
+                       return $message_id;
 
                $address = array();
                if ($data->location)
@@ -2121,6 +2172,7 @@ class diaspora {
 
                $datarray = array();
 
+               // Attach embedded pictures to the body
                if ($data->photo) {
                        foreach ($data->photo AS $photo)
                                $body = "[img]".unxmlify($photo->remote_photo_path).
@@ -2148,7 +2200,7 @@ class diaspora {
                $datarray["owner-avatar"] = $datarray["author-avatar"];
 
                $datarray["guid"] = $guid;
-               $datarray["uri"] = $datarray["parent-uri"] = $author.":".$guid;
+               $datarray["uri"] = $datarray["parent-uri"] = self::get_uri_from_guid($author, $guid);
 
                $datarray["verb"] = ACTIVITY_POST;
                $datarray["gravity"] = GRAVITY_PARENT;
@@ -2179,9 +2231,9 @@ class diaspora {
                return $message_id;
        }
 
-       /******************************************************************************************
+       /* ************************************************************************************** *
         * Here are all the functions that are needed to transmit data with the Diaspora protocol *
-        ******************************************************************************************/
+        * ************************************************************************************** */
 
        /**
         * @brief returnes the handle of a contact
@@ -2190,13 +2242,52 @@ class diaspora {
         *
         * @return string the handle in the format user@domain.tld
         */
-       private function my_handle($me) {
+       private function my_handle($contact) {
                if ($contact["addr"] != "")
                        return $contact["addr"];
 
                // Normally we should have a filled "addr" field - but in the past this wasn't the case
                // So - just in case - we build the the address here.
-               return $me["nickname"]."@".substr(App::get_baseurl(), strpos(App::get_baseurl(),"://") + 3);
+               if ($contact["nickname"] != "")
+                       $nick = $contact["nickname"];
+               else
+                       $nick = $contact["nick"];
+
+               return $nick."@".substr(App::get_baseurl(), strpos(App::get_baseurl(),"://") + 3);
+       }
+
+       /**
+        * @brief Creates the envelope for the "fetch" endpoint
+        *
+        * @param string $msg The message that is to be transmitted
+        * @param array $user The record of the sender
+        *
+        * @return string The envelope
+        */
+
+       function build_magic_envelope($msg, $user) {
+
+               $b64url_data = base64url_encode($msg);
+               $data = str_replace(array("\n", "\r", " ", "\t"), array("", "", "", ""), $b64url_data);
+
+               $key_id = base64url_encode(diaspora::my_handle($user));
+               $type = "application/xml";
+               $encoding = "base64url";
+               $alg = "RSA-SHA256";
+               $signable_data = $data.".".base64url_encode($type).".".base64url_encode($encoding).".".base64url_encode($alg);
+               $signature = rsa_sign($signable_data, $user["prvkey"]);
+               $sig = base64url_encode($signature);
+
+               $xmldata = array("me:env" => array("me:data" => $data,
+                                                       "@attributes" => array("type" => $type),
+                                                       "me:encoding" => $encoding,
+                                                       "me:alg" => $alg,
+                                                       "me:sig" => $sig,
+                                                       "@attributes2" => array("key_id" => $key_id)));
+
+               $namespaces = array("me" => "http://salmon-protocol.org/ns/magic-env");
+
+               return xml::from_array($xmldata, $xml, false, $namespaces);
        }
 
        /**
@@ -2230,11 +2321,11 @@ class diaspora {
                $sig = base64url_encode($signature);
 
                $xmldata = array("diaspora" => array("header" => array("author_id" => $handle),
-                                               "me:env" => array("me:encoding" => "base64url",
-                                                               "me:alg" => "RSA-SHA256",
-                                                               "me:data" => $data,
-                                                               "@attributes" => array("type" => "application/xml"),
-                                                               "me:sig" => $sig)));
+                                                       "me:env" => array("me:encoding" => $encoding,
+                                                       "me:alg" => $alg,
+                                                       "me:data" => $data,
+                                                       "@attributes" => array("type" => $type),
+                                                       "me:sig" => $sig)));
 
                $namespaces = array("" => "https://joindiaspora.com/protocol",
                                "me" => "http://salmon-protocol.org/ns/magic-env");
@@ -2320,10 +2411,10 @@ class diaspora {
                $cipher_json = base64_encode($encrypted_header_json_object);
 
                $xmldata = array("diaspora" => array("encrypted_header" => $cipher_json,
-                                               "me:env" => array("me:encoding" => "base64url",
-                                                               "me:alg" => "RSA-SHA256",
+                                               "me:env" => array("me:encoding" => $encoding,
+                                                               "me:alg" => $alg,
                                                                "me:data" => $data,
-                                                               "@attributes" => array("type" => "application/xml"),
+                                                               "@attributes" => array("type" => $type),
                                                                "me:sig" => $sig)));
 
                $namespaces = array("" => "https://joindiaspora.com/protocol",
@@ -2345,7 +2436,7 @@ class diaspora {
         * @param string $pubkey The public key of the receiver
         * @param bool $public Is the message public?
         *
-        * @return 
+        * @return string The message that will be transmitted to other servers
         */
        private function build_message($msg, $user, $contact, $prvkey, $pubkey, $public = false) {
 
@@ -2442,7 +2533,21 @@ class diaspora {
 
 
        /**
-        * @brief 
+        * @brief Build the post xml
+        *
+        * @param string $type The message type
+        * @param array $message The message data
+        *
+        * @return string The post XML
+        */
+       public static function build_post_xml($type, $message) {
+
+               $data = array("XML" => array("post" => array($type => $message)));
+               return xml::from_array($data, $xml);
+       }
+
+       /**
+        * @brief Builds and transmit messages
         *
         * @param array $owner the array of the item owner
         * @param array $contact Target of the communication
@@ -2456,9 +2561,7 @@ class diaspora {
         */
        private function build_and_transmit($owner, $contact, $type, $message, $public_batch = false, $guid = "", $spool = false) {
 
-               $data = array("XML" => array("post" => array($type => $message)));
-
-               $msg = xml::from_array($data, $xml);
+               $msg = self::build_post_xml($type, $message);
 
                logger('message: '.$msg, LOGGER_DATA);
                logger('send guid '.$guid, LOGGER_DEBUG);
@@ -2477,7 +2580,7 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Sends a "share" message
         *
         * @param array $owner the array of the item owner
         * @param array $contact Target of the communication
@@ -2493,7 +2596,7 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief sends an "unshare"
         *
         * @param array $owner the array of the item owner
         * @param array $contact Target of the communication
@@ -2522,7 +2625,7 @@ class diaspora {
 
                // Skip if it isn't a pure repeated messages
                // Does it start with a share?
-               if (strpos($body, "[share") > 0)
+               if ((strpos($body, "[share") > 0) AND $complete)
                        return(false);
 
                // Does it end with a share?
@@ -2583,22 +2686,23 @@ class diaspora {
                        $link = $matches[1];
 
                $ret["root_guid"] = preg_replace("=https?://(.*)/posts/(.*)=ism", "$2", $link);
-               if (($ret["root_guid"] == $link) OR ($ret["root_guid"] == ""))
+               if (($ret["root_guid"] == $link) OR (trim($ret["root_guid"]) == ""))
                        return(false);
+
                return($ret);
        }
 
        /**
-        * @brief 
+        * @brief Create a post (status message or reshare)
         *
         * @param array $item The item that will be exported
         * @param array $owner the array of the item owner
-        * @param array $contact Target of the communication
-        * @param bool $public_batch Is it a public post?
         *
-        * @return int The result of the transmission
+        * @return array
+        * 'type' -> Message type ("status_message" or "reshare")
+        * 'message' -> Array of XML elements of the status
         */
-       public static function send_status($item, $owner, $contact, $public_batch = false) {
+       public static function build_status($item, $owner) {
 
                $myaddr = self::my_handle($owner);
 
@@ -2661,17 +2765,33 @@ class diaspora {
 
                        $type = "status_message";
                }
+               return array("type" => $type, "message" => $message);
+       }
 
-               return self::build_and_transmit($owner, $contact, $type, $message, $public_batch, $item["guid"]);
+       /**
+        * @brief Sends a post
+        *
+        * @param array $item The item that will be exported
+        * @param array $owner the array of the item owner
+        * @param array $contact Target of the communication
+        * @param bool $public_batch Is it a public post?
+        *
+        * @return int The result of the transmission
+        */
+       public static function send_status($item, $owner, $contact, $public_batch = false) {
+
+               $status = diaspora::build_status($item, $owner);
+
+               return self::build_and_transmit($owner, $contact, $status["type"], $status["message"], $public_batch, $item["guid"]);
        }
 
        /**
-        * @brief 
+        * @brief Creates a "like" object
         *
         * @param array $item The item that will be exported
         * @param array $owner the array of the item owner
         *
-        * @return 
+        * @return array The data for a "like"
         */
        private function construct_like($item, $owner) {
 
@@ -2689,17 +2809,17 @@ class diaspora {
                                "guid" => $item["guid"],
                                "target_type" => $target_type,
                                "parent_guid" => $parent["guid"],
-                               "author_signature" => $authorsig,
+                               "author_signature" => "",
                                "diaspora_handle" => self::my_handle($owner)));
        }
 
        /**
-        * @brief 
+        * @brief Creates the object for a comment
         *
         * @param array $item The item that will be exported
         * @param array $owner the array of the item owner
         *
-        * @return 
+        * @return array The data for a comment
         */
        private function construct_comment($item, $owner) {
 
@@ -2801,7 +2921,7 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Relays messages (like, comment, retraction) to other servers if we are the thread owner
         *
         * @param array $item The item that will be exported
         * @param array $owner the array of the item owner
@@ -2905,7 +3025,7 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Sends a mail
         *
         * @param array $item The item that will be exported
         * @param array $owner The owner
@@ -2971,11 +3091,9 @@ class diaspora {
        }
 
        /**
-        * @brief 
+        * @brief Sends profile data
         *
         * @param int $uid The user id
-        *
-        * @return int The result of the transmission
         */
        public static function send_profile($uid) {
 
@@ -3054,5 +3172,106 @@ class diaspora {
                foreach($recips as $recip)
                        self::build_and_transmit($profile, $recip, "profile", $message, false, "", true);
        }
+
+       /**
+        * @brief Stores the signature for likes that are created on our system
+        *
+        * @param array $contact The contact array of the "like"
+        * @param int $post_id The post id of the "like"
+        *
+        * @return bool Success
+        */
+       public static function store_like_signature($contact, $post_id) {
+
+               // Is the contact the owner? Then fetch the private key
+               if (!$contact['self'] OR ($contact['uid'] == 0)) {
+                       logger("No owner post, so not storing signature", LOGGER_DEBUG);
+                       return false;
+               }
+
+               $r = q("SELECT `prvkey` FROM `user` WHERE `uid` = %d LIMIT 1", intval($contact['uid']));
+               if(!$r)
+                       return false;
+
+               $contact["uprvkey"] = $r[0]['prvkey'];
+
+               $r = q("SELECT * FROM `item` WHERE `id` = %d LIMIT 1", intval($post_id));
+               if (!$r)
+                       return false;
+
+               if (!in_array($r[0]["verb"], array(ACTIVITY_LIKE, ACTIVITY_DISLIKE)))
+                       return false;
+
+               $message = self::construct_like($r[0], $contact);
+               $message["author_signature"] = self::signature($contact, $message);
+
+               // In the future we will store the signature more flexible to support new fields.
+               // Right now we cannot change this since old Friendica versions (prior to 3.5) can only handle this format.
+               // (We are transmitting this data here via DFRN)
+
+               $signed_text = $message["positive"].";".$message["guid"].";".$message["target_type"].";".
+                               $message["parent_guid"].";".$message["diaspora_handle"];
+
+               q("INSERT INTO `sign` (`iid`,`signed_text`,`signature`,`signer`) VALUES (%d,'%s','%s','%s')",
+                       intval($post_id),
+                       dbesc($signed_text),
+                       dbesc($message["author_signature"]),
+                       dbesc($message["diaspora_handle"])
+               );
+
+               // This here will replace the lines above, once Diaspora changed its protocol
+               //q("INSERT INTO `sign` (`iid`,`signed_text`) VALUES (%d,'%s')",
+               //      intval($message_id),
+               //      dbesc(json_encode($message))
+               //);
+
+               logger('Stored diaspora like signature');
+               return true;
+       }
+
+       /**
+        * @brief Stores the signature for comments that are created on our system
+        *
+        * @param array $item The item array of the comment
+        * @param array $contact The contact array of the item owner
+        * @param string $uprvkey The private key of the sender
+        * @param int $message_id The message id of the comment
+        *
+        * @return bool Success
+        */
+       public static function store_comment_signature($item, $contact, $uprvkey, $message_id) {
+
+               if ($uprvkey == "") {
+                       logger('No private key, so not storing comment signature', LOGGER_DEBUG);
+                       return false;
+               }
+
+               $contact["uprvkey"] = $uprvkey;
+
+               $message = self::construct_comment($item, $contact);
+               $message["author_signature"] = self::signature($contact, $message);
+
+               // In the future we will store the signature more flexible to support new fields.
+               // Right now we cannot change this since old Friendica versions (prior to 3.5) can only handle this format.
+               // (We are transmitting this data here via DFRN)
+               $signed_text = $message["guid"].";".$message["parent_guid"].";".
+                               $message["text"].";".$message["diaspora_handle"];
+
+               q("INSERT INTO `sign` (`iid`,`signed_text`,`signature`,`signer`) VALUES (%d,'%s','%s','%s')",
+                       intval($message_id),
+                       dbesc($signed_text),
+                       dbesc($message["author_signature"]),
+                       dbesc($message["diaspora_handle"])
+               );
+
+               // This here will replace the lines above, once Diaspora changed its protocol
+               //q("INSERT INTO `sign` (`iid`,`signed_text`) VALUES (%d,'%s')",
+               //      intval($message_id),
+               //      dbesc(json_encode($message))
+               //);
+
+               logger('Stored diaspora comment signature');
+               return true;
+       }
 }
 ?>