Add a setting to restrict returning a full match unless in phonebook or same group

Signed-off-by: Joas Schilling <coding@schilljs.com>

apps/dav/lib/Connector/Sabre/Principal.php

 		$allowEnumeration = $this->shareManager->allowEnumeration();
 		$limitEnumerationGroup = $this->shareManager->limitEnumerationToGroups();
 		$limitEnumerationPhone = $this->shareManager->limitEnumerationToPhone();
+		$allowEnumerationFullMatch = $this->shareManager->allowEnumerationFullMatch();
 
 		// If sharing is restricted to group members only,
 		// return only members that have groups in common
 		foreach ($searchProperties as $prop => $value) {
 			switch ($prop) {
 				case '{http://sabredav.org/ns}email-address':
-					$users = $this->userManager->getByEmail($value);
-
 					if (!$allowEnumeration) {
-						$users = \array_filter($users, static function (IUser $user) use ($value) {
-							return $user->getEMailAddress() === $value;
-						});
+						if ($allowEnumerationFullMatch) {
+							$users = $this->userManager->getByEmail($value);
+							$users = \array_filter($users, static function (IUser $user) use ($value) {
+								return $user->getEMailAddress() === $value;
+							});
+						} else {
+							$users = [];
+						}
 					} else {
-						$users = \array_filter($users, function (IUser $user) use ($currentUser, $value, $limitEnumerationPhone, $limitEnumerationGroup, $currentUserGroups) {
-							if ($user->getEMailAddress() === $value) {
+						$users = $this->userManager->getByEmail($value);
+						$users = \array_filter($users, function (IUser $user) use ($currentUser, $value, $limitEnumerationPhone, $limitEnumerationGroup, $allowEnumerationFullMatch, $currentUserGroups) {
+							if ($allowEnumerationFullMatch && $user->getEMailAddress() === $value) {
 								return true;
 							}
 
 					break;
 
 				case '{DAV:}displayname':
-					$users = $this->userManager->searchDisplayName($value, $searchLimit);
 
 					if (!$allowEnumeration) {
-						$users = \array_filter($users, static function (IUser $user) use ($value) {
-							return $user->getDisplayName() === $value;
-						});
+						if ($allowEnumerationFullMatch) {
+							$users = $this->userManager->searchDisplayName($value, $searchLimit);
+							$users = \array_filter($users, static function (IUser $user) use ($value) {
+								return $user->getDisplayName() === $value;
+							});
+						} else {
+							$users = [];
+						}
 					} else {
-						$users = \array_filter($users, function (IUser $user) use ($currentUser, $value, $limitEnumerationPhone, $limitEnumerationGroup, $currentUserGroups) {
-							if ($user->getDisplayName() === $value) {
+						$users = $this->userManager->searchDisplayName($value, $searchLimit);
+						$users = \array_filter($users, function (IUser $user) use ($currentUser, $value, $limitEnumerationPhone, $limitEnumerationGroup, $allowEnumerationFullMatch, $currentUserGroups) {
+							if ($allowEnumerationFullMatch && $user->getDisplayName() === $value) {
 								return true;
 							}
 

apps/dav/tests/unit/Connector/Sabre/PrincipalTest.php

 			->method('shareWithGroupMembersOnly')
 			->willReturn(false);
 
+		$this->shareManager->expects($this->once())
+			->method('allowEnumerationFullMatch')
+			->willReturn(true);
+
 		$user2 = $this->createMock(IUser::class);
 		$user2->method('getUID')->willReturn('user2');
 		$user2->method('getDisplayName')->willReturn('User 2');
 			['{DAV:}displayname' => 'User 2']));
 	}
 
+	public function testSearchPrincipalWithEnumerationDisabledDisplaynameOnFullMatch() {
+		$this->shareManager->expects($this->once())
+			->method('shareAPIEnabled')
+			->willReturn(true);
+
+		$this->shareManager->expects($this->once())
+			->method('allowEnumeration')
+			->willReturn(false);
+
+		$this->shareManager->expects($this->once())
+			->method('shareWithGroupMembersOnly')
+			->willReturn(false);
+
+		$this->shareManager->expects($this->once())
+			->method('allowEnumerationFullMatch')
+			->willReturn(false);
+
+		$this->assertEquals([], $this->connector->searchPrincipals('principals/users',
+			['{DAV:}displayname' => 'User 2']));
+	}
+
 	public function testSearchPrincipalWithEnumerationDisabledEmail() {
 		$this->shareManager->expects($this->once())
 			->method('shareAPIEnabled')
 			->method('shareWithGroupMembersOnly')
 			->willReturn(false);
 
+		$this->shareManager->expects($this->once())
+			->method('allowEnumerationFullMatch')
+			->willReturn(true);
+
 		$user2 = $this->createMock(IUser::class);
 		$user2->method('getUID')->willReturn('user2');
 		$user2->method('getDisplayName')->willReturn('User 2');
 			['{http://sabredav.org/ns}email-address' => 'user2@foo.bar']));
 	}
 
+	public function testSearchPrincipalWithEnumerationDisabledEmailOnFullMatch() {
+		$this->shareManager->expects($this->once())
+			->method('shareAPIEnabled')
+			->willReturn(true);
+
+		$this->shareManager->expects($this->once())
+			->method('allowEnumeration')
+			->willReturn(false);
+
+		$this->shareManager->expects($this->once())
+			->method('shareWithGroupMembersOnly')
+			->willReturn(false);
+
+		$this->shareManager->expects($this->once())
+			->method('allowEnumerationFullMatch')
+			->willReturn(false);
+
+
+		$this->assertEquals([], $this->connector->searchPrincipals('principals/users',
+			['{http://sabredav.org/ns}email-address' => 'user2@foo.bar']));
+	}
+
 	public function testSearchPrincipalWithEnumerationLimitedDisplayname() {
 		$this->shareManager->expects($this->at(0))
 			->method('shareAPIEnabled')

apps/settings/lib/Settings/Admin/Sharing.php

 			'allowShareDialogUserEnumeration' => $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes'),
 			'restrictUserEnumerationToGroup' => $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_group', 'no'),
 			'restrictUserEnumerationToPhone' => $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_phone', 'no'),
+			'restrictUserEnumerationFullMatch' => $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_full_match', 'yes'),
 			'enforceLinkPassword' => Util::isPublicLinkPasswordRequired(),
 			'onlyShareWithGroupMembers' => $this->shareManager->shareWithGroupMembersOnly(),
 			'shareAPIEnabled' => $this->config->getAppValue('core', 'shareapi_enabled', 'yes'),

apps/settings/templates/settings/admin/sharing.php

 			<?php if ($_['allowShareDialogUserEnumeration'] === 'yes') {
 	print_unescaped('checked="checked"');
 } ?> />
-		<label for="shareapi_allow_share_dialog_user_enumeration"><?php p($l->t('Allow username autocompletion in share dialog (if this is disabled the full username or email address needs to be entered)'));?></label><br />
+		<label for="shareapi_allow_share_dialog_user_enumeration"><?php p($l->t('Allow username autocompletion in share dialog'));?></label><br />
 	</p>
 
 	<p id="shareapi_restrict_user_enumeration_to_group_setting" class="indent <?php if ($_['shareAPIEnabled'] === 'no' || $_['allowShareDialogUserEnumeration'] === 'no') {
 }?>">
 		<em><?php p($l->t('If autocompletion "same group" and "phonebook matches" are enabled a match in either is enough to show the user.'));?></em><br />
 	</p>
+	<p id="shareapi_restrict_user_enumeration_full_match_setting" class="indent <?php if ($_['shareAPIEnabled'] === 'no') {
+		p('hidden');
+	}?>">
+		<input type="checkbox" name="shareapi_restrict_user_enumeration_full_match" value="1" id="shareapi_restrict_user_enumeration_full_match" class="checkbox"
+				<?php if ($_['restrictUserEnumerationFullMatch'] === 'yes') {
+					print_unescaped('checked="checked"');
+				} ?> />
+		<label for="shareapi_restrict_user_enumeration_full_match"><?php p($l->t('Allow username autocompletion when entering the full name or email address (ignoring missing phonebook match and being in the same group)'));?></label><br />
+	</p>
 
 	<p>
 		<input type="checkbox" id="publicShareDisclaimer" class="checkbox noJSAutoUpdate"

apps/settings/tests/Settings/Admin/SharingTest.php

 				['core', 'shareapi_allow_share_dialog_user_enumeration', 'yes', 'yes'],
 				['core', 'shareapi_restrict_user_enumeration_to_group', 'no', 'no'],
 				['core', 'shareapi_restrict_user_enumeration_to_phone', 'no', 'no'],
+				['core', 'shareapi_restrict_user_enumeration_full_match', 'yes', 'yes'],
 				['core', 'shareapi_enabled', 'yes', 'yes'],
 				['core', 'shareapi_default_expire_date', 'no', 'no'],
 				['core', 'shareapi_expire_after_n_days', '7', '7'],
 				'allowShareDialogUserEnumeration' => 'yes',
 				'restrictUserEnumerationToGroup' => 'no',
 				'restrictUserEnumerationToPhone' => 'no',
+				'restrictUserEnumerationFullMatch' => 'yes',
 				'enforceLinkPassword' => false,
 				'onlyShareWithGroupMembers' => false,
 				'shareAPIEnabled' => 'yes',
 				['core', 'shareapi_allow_share_dialog_user_enumeration', 'yes', 'yes'],
 				['core', 'shareapi_restrict_user_enumeration_to_group', 'no', 'no'],
 				['core', 'shareapi_restrict_user_enumeration_to_phone', 'no', 'no'],
+				['core', 'shareapi_restrict_user_enumeration_full_match', 'yes', 'yes'],
 				['core', 'shareapi_enabled', 'yes', 'yes'],
 				['core', 'shareapi_default_expire_date', 'no', 'no'],
 				['core', 'shareapi_expire_after_n_days', '7', '7'],
 				'allowShareDialogUserEnumeration' => 'yes',
 				'restrictUserEnumerationToGroup' => 'no',
 				'restrictUserEnumerationToPhone' => 'no',
+				'restrictUserEnumerationFullMatch' => 'yes',
 				'enforceLinkPassword' => false,
 				'onlyShareWithGroupMembers' => false,
 				'shareAPIEnabled' => 'yes',

build/integration/collaboration_features/autocomplete.feature

     Given using api version "2"
     And group "commongroup" exists
     And user "admin" belongs to group "commongroup"
+    And user "auto" exists
     And user "autocomplete" exists
     And user "autocomplete2" exists
     And user "autocomplete2" belongs to group "commongroup"
     When parameter "shareapi_allow_share_dialog_user_enumeration" of app "core" is set to "no"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
     Then get autocomplete for "autocomplete"
       | id | source |
       | autocomplete | users |
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
+    Then get autocomplete for "auto"
+      | id | source |
+    Then get autocomplete for "autocomplete"
+      | id | source |
 
 
   Scenario: getting autocomplete with limited enumeration by group
     When parameter "shareapi_restrict_user_enumeration_to_group" of app "core" is set to "yes"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
       | autocomplete2 | users |
     Then get autocomplete for "autocomplete"
       | id | source |
     Then get autocomplete for "autocomplete2"
       | id | source |
       | autocomplete2 | users |
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
+    Then get autocomplete for "autocomplete"
+      | id | source |
+      | autocomplete2 | users |
+    Then get autocomplete for "autocomplete2"
+      | id | source |
+      | autocomplete2 | users |
 
 
   Scenario: getting autocomplete with limited enumeration by phone
     When parameter "shareapi_restrict_user_enumeration_to_phone" of app "core" is set to "yes"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
 
     # autocomplete stores their phone number
     Given As an "autocomplete"
     Given As an "admin"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
 
     # admin populates they have the phone number
     When search users by phone for region "DE" with
       | random-string1 | 0711 / 252 428-90 |
+    Then get autocomplete for "auto"
+      | id | source |
+      | auto | users |
+      | autocomplete | users |
+
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
     Then get autocomplete for "auto"
       | id | source |
       | autocomplete | users |
     When search users by phone for region "DE" with
       | random-string1 | 0711 / 252 428-90 |
 
+    Then get autocomplete for "auto"
+      | id | source |
+      | auto | users |
+      | autocomplete | users |
+      | autocomplete2 | users |
+
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
     Then get autocomplete for "auto"
       | id | source |
       | autocomplete | users |
 
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
       | autocomplete | users |
       | autocomplete2 | users |
     When parameter "shareapi_only_share_with_group_members" of app "core" is set to "yes"
     When parameter "shareapi_restrict_user_enumeration_to_phone" of app "core" is set to "yes"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
 
     # autocomplete stores their phone number
     Given As an "autocomplete"
     Given As an "admin"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
 
     # admin populates they have the phone number
     When search users by phone for region "DE" with
       | random-string1 | 0711 / 252 428-90 |
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
       | autocomplete | users |
 
     # autocomplete changes their phone number
     Given As an "admin"
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
 
     # admin populates they have the new phone number
     When search users by phone for region "DE" with
       | random-string1 | 0711 / 252 428-91 |
     Then get autocomplete for "auto"
       | id | source |
+      | auto | users |
       | autocomplete | users |
 
 

build/integration/features/bootstrap/CollaborationContext.php

 		$this->deleteServerConfig('core', 'shareapi_allow_share_dialog_user_enumeration');
 		$this->deleteServerConfig('core', 'shareapi_restrict_user_enumeration_to_group');
 		$this->deleteServerConfig('core', 'shareapi_restrict_user_enumeration_to_phone');
+		$this->deleteServerConfig('core', 'shareapi_restrict_user_enumeration_full_match');
 		$this->deleteServerConfig('core', 'shareapi_only_share_with_group_members');
 	}
 }

lib/private/Collaboration/Collaborators/MailPlugin.php

 	protected $shareeEnumerationInGroupOnly;
 	/* @var bool */
 	protected $shareeEnumerationPhone;
+	/* @var bool */
+	protected $shareeEnumerationFullMatch;
 
 	/** @var IManager */
 	private $contactsManager;
 		$this->shareWithGroupOnly = $this->config->getAppValue('core', 'shareapi_only_share_with_group_members', 'no') === 'yes';
 		$this->shareeEnumerationInGroupOnly = $this->shareeEnumeration && $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_group', 'no') === 'yes';
 		$this->shareeEnumerationPhone = $this->shareeEnumeration && $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_phone', 'no') === 'yes';
+		$this->shareeEnumerationFullMatch = $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_full_match', 'yes') === 'yes';
 	}
 
 	/**
 								continue;
 							}
 						}
-						if ($exactEmailMatch) {
+						if ($exactEmailMatch && $this->shareeEnumerationFullMatch) {
 							try {
 								$cloud = $this->cloudIdManager->resolveCloudId($contact['CLOUD'][0]);
 							} catch (\InvalidArgumentException $e) {

lib/private/Collaboration/Collaborators/UserPlugin.php

 	protected $shareeEnumerationInGroupOnly;
 	/* @var bool */
 	protected $shareeEnumerationPhone;
+	/* @var bool */
+	protected $shareeEnumerationFullMatch;
 
 	/** @var IConfig */
 	private $config;
 		$this->shareeEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') === 'yes';
 		$this->shareeEnumerationInGroupOnly = $this->shareeEnumeration && $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_group', 'no') === 'yes';
 		$this->shareeEnumerationPhone = $this->shareeEnumeration && $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_phone', 'no') === 'yes';
+		$this->shareeEnumerationFullMatch = $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_full_match', 'yes') === 'yes';
 	}
 
 	public function search($search, $limit, $offset, ISearchResult $searchResult) {
 
 
 			if (
+				$this->shareeEnumerationFullMatch &&
 				$lowerSearch !== '' && (strtolower($uid) === $lowerSearch ||
 				strtolower($userDisplayName) === $lowerSearch ||
 				strtolower($userEmail) === $lowerSearch)
 			}
 		}
 
-		if ($offset === 0 && !$foundUserById) {
+		if ($this->shareeEnumerationFullMatch && $offset === 0 && !$foundUserById) {
 			// On page one we try if the search result has a direct hit on the
 			// user id and if so, we add that to the exact match list
 			$user = $this->userManager->get($search);

lib/private/Contacts/ContactsMenu/ContactsStore.php

 		$disallowEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') !== 'yes';
 		$restrictEnumerationGroup = $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_group', 'no') === 'yes';
 		$restrictEnumerationPhone = $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_phone', 'no') === 'yes';
+		$allowEnumerationFullMatch = $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_full_match', 'yes') === 'yes';
 		$excludedGroups = $this->config->getAppValue('core', 'shareapi_exclude_groups', 'no') === 'yes';
 
 		// whether to filter out local users
 
 		$selfUID = $self->getUID();
 
-		return array_values(array_filter($entries, function (IEntry $entry) use ($skipLocal, $ownGroupsOnly, $selfGroups, $selfUID, $disallowEnumeration, $restrictEnumerationGroup, $restrictEnumerationPhone, $filter) {
+		return array_values(array_filter($entries, function (IEntry $entry) use ($skipLocal, $ownGroupsOnly, $selfGroups, $selfUID, $disallowEnumeration, $restrictEnumerationGroup, $restrictEnumerationPhone, $allowEnumerationFullMatch, $filter) {
 			if ($entry->getProperty('UID') === $selfUID) {
 				return false;
 			}
 
 				// Prevent enumerating local users
 				if ($disallowEnumeration) {
+					if (!$allowEnumerationFullMatch) {
+						return false;
+					}
+
 					$filterUser = true;
 
 					$mailAddresses = $entry->getEMailAddresses();

lib/private/Share20/Manager.php

 			$this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_to_phone', 'no') === 'yes';
 	}
 
+	public function allowEnumerationFullMatch(): bool {
+		return $this->config->getAppValue('core', 'shareapi_restrict_user_enumeration_full_match', 'yes') === 'yes';
+	}
+
 	/**
 	 * Copied from \OC_Util::isSharingDisabledForUser
 	 *

lib/public/Share/IManager.php

 	 */
 	public function limitEnumerationToPhone(): bool;
 
+	/**
+	 * Check if user enumeration is allowed to return on full match
+	 *
+	 * @return bool
+	 * @since 21.0.1
+	 */
+	public function allowEnumerationFullMatch(): bool;
+
 	/**
 	 * Check if sharing is disabled for the given user
 	 *

tests/lib/Contacts/ContactsMenu/ContactsStoreTest.php

 	}
 
 	public function testGetContactsWithFilter() {
-		$this->config->expects($this->at(0))->method('getAppValue')
-			->with($this->equalTo('core'), $this->equalTo('shareapi_allow_share_dialog_user_enumeration'), $this->equalTo('yes'))
-			->willReturn('no');
+		$this->config
+			->method('getAppValue')
+			->willReturnMap([
+				['core', 'shareapi_allow_share_dialog_user_enumeration', 'yes', 'no'],
+				['core', 'shareapi_restrict_user_enumeration_full_match', 'yes', 'yes'],
+			]);
 
 		/** @var IUser|\PHPUnit\Framework\MockObject\MockObject $user */
 		$user = $this->createMock(IUser::class);
 		], $entry[0]->getEMailAddresses());
 	}
 
+	public function testGetContactsWithFilterWithoutFullMatch() {
+		$this->config
+			->method('getAppValue')
+			->willReturnMap([
+				['core', 'shareapi_allow_share_dialog_user_enumeration', 'yes', 'no'],
+				['core', 'shareapi_restrict_user_enumeration_full_match', 'yes', 'no'],
+			]);
+
+		/** @var IUser|\PHPUnit\Framework\MockObject\MockObject $user */
+		$user = $this->createMock(IUser::class);
+		$this->contactsManager->expects($this->any())
+			->method('search')
+			->willReturn([
+				[
+					'UID' => 'a567',
+					'FN' => 'Darren Roner',
+					'EMAIL' => [
+						'darren@roner.au',
+					],
+					'isLocalSystemBook' => true,
+				],
+				[
+					'UID' => 'john',
+					'FN' => 'John Doe',
+					'EMAIL' => [
+						'john@example.com',
+					],
+					'isLocalSystemBook' => true,
+				],
+				[
+					'FN' => 'Anne D',
+					'EMAIL' => [
+						'anne@example.com',
+					],
+					'isLocalSystemBook' => false,
+				],
+			]);
+		$user->expects($this->any())
+			->method('getUID')
+			->willReturn('user123');
+
+		// Complete match on UID should not match
+		$entry = $this->contactsStore->getContacts($user, 'a567');
+		$this->assertSame(1, count($entry));
+		$this->assertEquals([
+			'anne@example.com'
+		], $entry[0]->getEMailAddresses());
+
+		// Partial match on UID should not match
+		$entry = $this->contactsStore->getContacts($user, 'a56');
+		$this->assertSame(1, count($entry));
+		$this->assertEquals([
+			'anne@example.com'
+		], $entry[0]->getEMailAddresses());
+
+		// Complete match on email should not match
+		$entry = $this->contactsStore->getContacts($user, 'john@example.com');
+		$this->assertSame(1, count($entry));
+		$this->assertEquals([
+			'anne@example.com'
+		], $entry[0]->getEMailAddresses());
+
+		// Partial match on email should not match
+		$entry = $this->contactsStore->getContacts($user, 'john@example.co');
+		$this->assertSame(1, count($entry));
+		$this->assertEquals([
+			'anne@example.com'
+		], $entry[0]->getEMailAddresses());
+
+		// Match on FN should not match
+		$entry = $this->contactsStore->getContacts($user, 'Darren Roner');
+		$this->assertSame(1, count($entry));
+		$this->assertEquals([
+			'anne@example.com'
+		], $entry[0]->getEMailAddresses());
+
+		// Don't filter users in local addressbook
+		$entry = $this->contactsStore->getContacts($user, 'Anne D');
+		$this->assertSame(1, count($entry));
+		$this->assertEquals([
+			'anne@example.com'
+		], $entry[0]->getEMailAddresses());
+	}
+
 	public function testFindOneUser() {
 		$this->config->expects($this->at(0))->method('getAppValue')
 			->with($this->equalTo('core'), $this->equalTo('shareapi_allow_share_dialog_user_enumeration'), $this->equalTo('yes'))