From ebb9f1d16a1b4f91c12cc4092218e8f4ff2a25a2 Mon Sep 17 00:00:00 2001
From: Joas Schilling <coding@schilljs.com>
Date: Tue, 9 Mar 2021 20:31:28 +0100
Subject: [PATCH] Add a KnownUsers database with model

Signed-off-by: Joas Schilling <coding@schilljs.com>
---
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 apps/dav/composer/composer/ClassLoader.php    |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 apps/files/composer/composer/ClassLoader.php  |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 apps/oauth2/composer/composer/ClassLoader.php |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../testing/composer/composer/ClassLoader.php |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../composer/composer/ClassLoader.php         |  6 +-
 .../Version21000Date20210309185126.php        | 69 ++++++++++++++++++
 lib/composer/composer/ClassLoader.php         |  6 +-
 lib/composer/composer/autoload_classmap.php   |  3 +
 lib/composer/composer/autoload_static.php     |  3 +
 lib/private/KnownUser/KnownUser.php           | 46 ++++++++++++
 lib/private/KnownUser/KnownUserMapper.php     | 72 +++++++++++++++++++
 31 files changed, 297 insertions(+), 52 deletions(-)
 create mode 100644 core/Migrations/Version21000Date20210309185126.php
 create mode 100644 lib/private/KnownUser/KnownUser.php
 create mode 100644 lib/private/KnownUser/KnownUserMapper.php

diff --git a/apps/accessibility/composer/composer/ClassLoader.php b/apps/accessibility/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/accessibility/composer/composer/ClassLoader.php
+++ b/apps/accessibility/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/admin_audit/composer/composer/ClassLoader.php b/apps/admin_audit/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/admin_audit/composer/composer/ClassLoader.php
+++ b/apps/admin_audit/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/cloud_federation_api/composer/composer/ClassLoader.php b/apps/cloud_federation_api/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/cloud_federation_api/composer/composer/ClassLoader.php
+++ b/apps/cloud_federation_api/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/comments/composer/composer/ClassLoader.php b/apps/comments/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/comments/composer/composer/ClassLoader.php
+++ b/apps/comments/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/contactsinteraction/composer/composer/ClassLoader.php b/apps/contactsinteraction/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/contactsinteraction/composer/composer/ClassLoader.php
+++ b/apps/contactsinteraction/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/dav/composer/composer/ClassLoader.php b/apps/dav/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/dav/composer/composer/ClassLoader.php
+++ b/apps/dav/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/encryption/composer/composer/ClassLoader.php b/apps/encryption/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/encryption/composer/composer/ClassLoader.php
+++ b/apps/encryption/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/federatedfilesharing/composer/composer/ClassLoader.php b/apps/federatedfilesharing/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/federatedfilesharing/composer/composer/ClassLoader.php
+++ b/apps/federatedfilesharing/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/federation/composer/composer/ClassLoader.php b/apps/federation/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/federation/composer/composer/ClassLoader.php
+++ b/apps/federation/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/files/composer/composer/ClassLoader.php b/apps/files/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/files/composer/composer/ClassLoader.php
+++ b/apps/files/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/files_sharing/composer/composer/ClassLoader.php b/apps/files_sharing/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/files_sharing/composer/composer/ClassLoader.php
+++ b/apps/files_sharing/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/files_trashbin/composer/composer/ClassLoader.php b/apps/files_trashbin/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/files_trashbin/composer/composer/ClassLoader.php
+++ b/apps/files_trashbin/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/files_versions/composer/composer/ClassLoader.php b/apps/files_versions/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/files_versions/composer/composer/ClassLoader.php
+++ b/apps/files_versions/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/lookup_server_connector/composer/composer/ClassLoader.php b/apps/lookup_server_connector/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/lookup_server_connector/composer/composer/ClassLoader.php
+++ b/apps/lookup_server_connector/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/oauth2/composer/composer/ClassLoader.php b/apps/oauth2/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/oauth2/composer/composer/ClassLoader.php
+++ b/apps/oauth2/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/provisioning_api/composer/composer/ClassLoader.php b/apps/provisioning_api/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/provisioning_api/composer/composer/ClassLoader.php
+++ b/apps/provisioning_api/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/settings/composer/composer/ClassLoader.php b/apps/settings/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/settings/composer/composer/ClassLoader.php
+++ b/apps/settings/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/sharebymail/composer/composer/ClassLoader.php b/apps/sharebymail/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/sharebymail/composer/composer/ClassLoader.php
+++ b/apps/sharebymail/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/systemtags/composer/composer/ClassLoader.php b/apps/systemtags/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/systemtags/composer/composer/ClassLoader.php
+++ b/apps/systemtags/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/testing/composer/composer/ClassLoader.php b/apps/testing/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/testing/composer/composer/ClassLoader.php
+++ b/apps/testing/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/twofactor_backupcodes/composer/composer/ClassLoader.php b/apps/twofactor_backupcodes/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/twofactor_backupcodes/composer/composer/ClassLoader.php
+++ b/apps/twofactor_backupcodes/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/updatenotification/composer/composer/ClassLoader.php b/apps/updatenotification/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/updatenotification/composer/composer/ClassLoader.php
+++ b/apps/updatenotification/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/user_ldap/composer/composer/ClassLoader.php b/apps/user_ldap/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/user_ldap/composer/composer/ClassLoader.php
+++ b/apps/user_ldap/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/user_status/composer/composer/ClassLoader.php b/apps/user_status/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/user_status/composer/composer/ClassLoader.php
+++ b/apps/user_status/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/apps/workflowengine/composer/composer/ClassLoader.php b/apps/workflowengine/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/apps/workflowengine/composer/composer/ClassLoader.php
+++ b/apps/workflowengine/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/core/Migrations/Version21000Date20210309185126.php b/core/Migrations/Version21000Date20210309185126.php
new file mode 100644
index 00000000000..675cda9e03f
--- /dev/null
+++ b/core/Migrations/Version21000Date20210309185126.php
@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Joas Schilling <coding@schilljs.com>
+ *
+ * @author Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace OC\Core\Migrations;
+
+use Closure;
+use Doctrine\DBAL\Types\Types;
+use OCP\DB\ISchemaWrapper;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+
+class Version21000Date20210309185126 extends SimpleMigrationStep {
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 */
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options): ?ISchemaWrapper {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		if (!$schema->hasTable('known_users')) {
+			$table = $schema->createTable('known_users');
+
+			// Auto increment id
+			$table->addColumn('id', Types::BIGINT, [
+				'autoincrement' => true,
+				'notnull' => true,
+			]);
+
+			$table->addColumn('known_to', Types::STRING, [
+				'notnull' => true,
+				'length' => 255,
+			]);
+			$table->addColumn('known_user', Types::STRING, [
+				'notnull' => true,
+				'length' => 255,
+			]);
+
+			$table->setPrimaryKey(['id']);
+			$table->addIndex(['known_to'], 'ku_known_to');
+			return $schema;
+		}
+
+		return null;
+	}
+}
diff --git a/lib/composer/composer/ClassLoader.php b/lib/composer/composer/ClassLoader.php
index 4d989a212c9..247294d66ee 100644
--- a/lib/composer/composer/ClassLoader.php
+++ b/lib/composer/composer/ClassLoader.php
@@ -311,8 +311,10 @@ class ClassLoader
         spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 
         if (null === $this->vendorDir) {
-            //no-op
-        } elseif ($prepend) {
+            return;
+        }
+
+        if ($prepend) {
             self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
         } else {
             unset(self::$registeredLoaders[$this->vendorDir]);
diff --git a/lib/composer/composer/autoload_classmap.php b/lib/composer/composer/autoload_classmap.php
index 49b138714a7..bfac8495018 100644
--- a/lib/composer/composer/autoload_classmap.php
+++ b/lib/composer/composer/autoload_classmap.php
@@ -950,6 +950,7 @@ return array(
     'OC\\Core\\Migrations\\Version21000Date20201120141228' => $baseDir . '/core/Migrations/Version21000Date20201120141228.php',
     'OC\\Core\\Migrations\\Version21000Date20201202095923' => $baseDir . '/core/Migrations/Version21000Date20201202095923.php',
     'OC\\Core\\Migrations\\Version21000Date20210119195004' => $baseDir . '/core/Migrations/Version21000Date20210119195004.php',
+    'OC\\Core\\Migrations\\Version21000Date20210309185126' => $baseDir . '/core/Migrations/Version21000Date20210309185126.php',
     'OC\\Core\\Notification\\CoreNotifier' => $baseDir . '/core/Notification/CoreNotifier.php',
     'OC\\Core\\Service\\LoginFlowV2Service' => $baseDir . '/core/Service/LoginFlowV2Service.php',
     'OC\\DB\\Adapter' => $baseDir . '/lib/private/DB/Adapter.php',
@@ -1168,6 +1169,8 @@ return array(
     'OC\\IntegrityCheck\\Helpers\\FileAccessHelper' => $baseDir . '/lib/private/IntegrityCheck/Helpers/FileAccessHelper.php',
     'OC\\IntegrityCheck\\Iterator\\ExcludeFileByNameFilterIterator' => $baseDir . '/lib/private/IntegrityCheck/Iterator/ExcludeFileByNameFilterIterator.php',
     'OC\\IntegrityCheck\\Iterator\\ExcludeFoldersByPathFilterIterator' => $baseDir . '/lib/private/IntegrityCheck/Iterator/ExcludeFoldersByPathFilterIterator.php',
+    'OC\\KnownUser\\KnownUser' => $baseDir . '/lib/private/KnownUser/KnownUser.php',
+    'OC\\KnownUser\\KnownUserMapper' => $baseDir . '/lib/private/KnownUser/KnownUserMapper.php',
     'OC\\L10N\\Factory' => $baseDir . '/lib/private/L10N/Factory.php',
     'OC\\L10N\\L10N' => $baseDir . '/lib/private/L10N/L10N.php',
     'OC\\L10N\\L10NString' => $baseDir . '/lib/private/L10N/L10NString.php',
diff --git a/lib/composer/composer/autoload_static.php b/lib/composer/composer/autoload_static.php
index 373db9144bd..349b84fdcf8 100644
--- a/lib/composer/composer/autoload_static.php
+++ b/lib/composer/composer/autoload_static.php
@@ -979,6 +979,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OC\\Core\\Migrations\\Version21000Date20201120141228' => __DIR__ . '/../../..' . '/core/Migrations/Version21000Date20201120141228.php',
         'OC\\Core\\Migrations\\Version21000Date20201202095923' => __DIR__ . '/../../..' . '/core/Migrations/Version21000Date20201202095923.php',
         'OC\\Core\\Migrations\\Version21000Date20210119195004' => __DIR__ . '/../../..' . '/core/Migrations/Version21000Date20210119195004.php',
+        'OC\\Core\\Migrations\\Version21000Date20210309185126' => __DIR__ . '/../../..' . '/core/Migrations/Version21000Date20210309185126.php',
         'OC\\Core\\Notification\\CoreNotifier' => __DIR__ . '/../../..' . '/core/Notification/CoreNotifier.php',
         'OC\\Core\\Service\\LoginFlowV2Service' => __DIR__ . '/../../..' . '/core/Service/LoginFlowV2Service.php',
         'OC\\DB\\Adapter' => __DIR__ . '/../../..' . '/lib/private/DB/Adapter.php',
@@ -1197,6 +1198,8 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OC\\IntegrityCheck\\Helpers\\FileAccessHelper' => __DIR__ . '/../../..' . '/lib/private/IntegrityCheck/Helpers/FileAccessHelper.php',
         'OC\\IntegrityCheck\\Iterator\\ExcludeFileByNameFilterIterator' => __DIR__ . '/../../..' . '/lib/private/IntegrityCheck/Iterator/ExcludeFileByNameFilterIterator.php',
         'OC\\IntegrityCheck\\Iterator\\ExcludeFoldersByPathFilterIterator' => __DIR__ . '/../../..' . '/lib/private/IntegrityCheck/Iterator/ExcludeFoldersByPathFilterIterator.php',
+        'OC\\KnownUser\\KnownUser' => __DIR__ . '/../../..' . '/lib/private/KnownUser/KnownUser.php',
+        'OC\\KnownUser\\KnownUserMapper' => __DIR__ . '/../../..' . '/lib/private/KnownUser/KnownUserMapper.php',
         'OC\\L10N\\Factory' => __DIR__ . '/../../..' . '/lib/private/L10N/Factory.php',
         'OC\\L10N\\L10N' => __DIR__ . '/../../..' . '/lib/private/L10N/L10N.php',
         'OC\\L10N\\L10NString' => __DIR__ . '/../../..' . '/lib/private/L10N/L10NString.php',
diff --git a/lib/private/KnownUser/KnownUser.php b/lib/private/KnownUser/KnownUser.php
new file mode 100644
index 00000000000..939c9199c79
--- /dev/null
+++ b/lib/private/KnownUser/KnownUser.php
@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC\KnownUser;
+
+use OCP\AppFramework\Db\Entity;
+
+/**
+ * @method void setKnownTo(string $knownTo)
+ * @method string getKnownTo()
+ * @method void setKnownUser(string $knownUser)
+ * @method string getKnownUser()
+ */
+class KnownUser extends Entity {
+
+	/** @var string */
+	protected $knownTo;
+
+	/** @var string */
+	protected $knownUser;
+
+	public function __construct() {
+		$this->addType('knownTo', 'string');
+		$this->addType('knownUser', 'string');
+	}
+}
diff --git a/lib/private/KnownUser/KnownUserMapper.php b/lib/private/KnownUser/KnownUserMapper.php
new file mode 100644
index 00000000000..86e13a2e2f0
--- /dev/null
+++ b/lib/private/KnownUser/KnownUserMapper.php
@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC\KnownUser;
+
+use OCP\AppFramework\Db\QBMapper;
+use OCP\IDBConnection;
+
+/**
+ * @method KnownUser mapRowToEntity(array $row)
+ */
+class KnownUserMapper extends QBMapper {
+
+	/**
+	 * @param IDBConnection $db
+	 */
+	public function __construct(IDBConnection $db) {
+		parent::__construct($db, 'known_users', KnownUser::class);
+	}
+
+	/**
+	 * @param string $knownTo
+	 * @return int Number of deleted entities
+	 */
+	public function deleteKnownTo(string $knownTo): int {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where($query->expr()->eq('known_to', $query->createNamedParameter($knownTo)));
+
+		return (int) $query->execute();
+	}
+
+	/**
+	 * @param string $knownUser
+	 * @return int Number of deleted entities
+	 */
+	public function deleteKnownUser(string $knownUser): int {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where($query->expr()->eq('known_user', $query->createNamedParameter($knownUser)));
+
+		return (int) $query->execute();
+	}
+
+	public function createKnownUserFromRow(array $row): KnownUser {
+		return $this->mapRowToEntity([
+			'id' => $row['s_id'],
+			'known_to' => $row['known_to'],
+			'known_user' => $row['known_user'],
+		]);
+	}
+}
-- 
GitLab