Make it possible to enforce mandatory 2FA for groups

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

3 files changed, 158 insertions, 6 deletions

diff --git a/lib/private/Authentication/TwoFactorAuth/EnforcementState.php b/lib/private/Authentication/TwoFactorAuth/EnforcementState.php
new file mode 100644
index 00000000000..11a3d2c4105
--- /dev/null
+++ b/lib/private/Authentication/TwoFactorAuth/EnforcementState.php
@@ -0,0 +1,85 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2018 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2018 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @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\Authentication\TwoFactorAuth;
+
+use JsonSerializable;
+
+class EnforcementState implements JsonSerializable {
+
+	/** @var bool */
+	private $enforced;
+
+	/** @var array */
+	private $enforcedGroups;
+
+	/** @var array */
+	private $excludedGroups;
+
+	/**
+	 * EnforcementState constructor.
+	 *
+	 * @param bool $enforced
+	 * @param string[] $enforcedGroups
+	 * @param string[] $excludedGroups
+	 */
+	public function __construct(bool $enforced,
+								array $enforcedGroups = [],
+								array $excludedGroups = []) {
+		$this->enforced = $enforced;
+		$this->enforcedGroups = $enforcedGroups;
+		$this->excludedGroups = $excludedGroups;
+	}
+
+	/**
+	 * @return string[]
+	 */
+	public function isEnforced(): bool {
+		return $this->enforced;
+	}
+
+	/**
+	 * @return string[]
+	 */
+	public function getEnforcedGroups(): array {
+		return $this->enforcedGroups;
+	}
+
+	/**
+	 * @return string[]
+	 */
+	public function getExcludedGroups(): array {
+		return $this->excludedGroups;
+	}
+
+	public function jsonSerialize(): array {
+		return [
+			'enforced' => $this->enforced,
+			'enforcedGroups' => $this->enforcedGroups,
+			'excludedGroups' => $this->excludedGroups,
+		];
+	}
+
+}
diff --git a/lib/private/Authentication/TwoFactorAuth/Manager.php b/lib/private/Authentication/TwoFactorAuth/Manager.php
index 2307a731002..56fca8a745c 100644
--- a/lib/private/Authentication/TwoFactorAuth/Manager.php
+++ b/lib/private/Authentication/TwoFactorAuth/Manager.php
@@ -106,7 +106,7 @@ class Manager {
 	 * @return boolean
 	 */
 	public function isTwoFactorAuthenticated(IUser $user): bool {
-		if ($this->mandatoryTwoFactor->isEnforced()) {
+		if ($this->mandatoryTwoFactor->isEnforcedFor($user)) {
 			return true;
 		}
 
diff --git a/lib/private/Authentication/TwoFactorAuth/MandatoryTwoFactor.php b/lib/private/Authentication/TwoFactorAuth/MandatoryTwoFactor.php
index a23a10a1be6..45dcb8655c1 100644
--- a/lib/private/Authentication/TwoFactorAuth/MandatoryTwoFactor.php
+++ b/lib/private/Authentication/TwoFactorAuth/MandatoryTwoFactor.php
@@ -27,22 +27,89 @@ declare(strict_types=1);
 namespace OC\Authentication\TwoFactorAuth;
 
 use OCP\IConfig;
+use OCP\IGroupManager;
+use OCP\IUser;
 
 class MandatoryTwoFactor {
 
 	/** @var IConfig */
 	private $config;
 
-	public function __construct(IConfig $config) {
+	/** @var IGroupManager */
+	private $groupManager;
+
+	public function __construct(IConfig $config, IGroupManager $groupManager) {
 		$this->config = $config;
+		$this->groupManager = $groupManager;
 	}
 
-	public function isEnforced(): bool {
-		return $this->config->getSystemValue('twofactor_enforced', 'false') === 'true';
+	/**
+	 * Get the state of enforced two-factor auth
+	 */
+	public function getState(): EnforcementState {
+		return new EnforcementState(
+			$this->config->getSystemValue('twofactor_enforced', 'false') === 'true',
+			$this->config->getSystemValue('twofactor_enforced_groups', []),
+			$this->config->getSystemValue('twofactor_enforced_excluded_groups', [])
+		);
 	}
 
-	public function setEnforced(bool $enforced) {
-		$this->config->setSystemValue('twofactor_enforced', $enforced ? 'true' : 'false');
+	/**
+	 * Set the state of enforced two-factor auth
+	 */
+	public function setState(EnforcementState $state) {
+		$this->config->setSystemValue('twofactor_enforced', $state->isEnforced() ? 'true' : 'false');
+		$this->config->setSystemValue('twofactor_enforced_groups', $state->getEnforcedGroups());
+		$this->config->setSystemValue('twofactor_enforced_excluded_groups', $state->getExcludedGroups());
 	}
 
+	/**
+	 * Check if two-factor auth is enforced for a specific user
+	 *
+	 * The admin(s) can enforce two-factor auth system-wide, for certain groups only
+	 * and also have the option to exclude users of certain groups. This method will
+	 * check their membership of those groups.
+	 *
+	 * @param IUser $user
+	 *
+	 * @return bool
+	 */
+	public function isEnforcedFor(IUser $user): bool {
+		$state = $this->getState();
+		if (!$state->isEnforced()) {
+			return false;
+		}
+		$uid = $user->getUID();
+
+		/*
+		 * If there is a list of enforced groups, we only enforce 2FA for members of those groups.
+		 * For all the other users it is not enforced (overruling the excluded groups list).
+		 */
+		if (!empty($state->getEnforcedGroups())) {
+			foreach ($state->getEnforcedGroups() as $group) {
+				if ($this->groupManager->isInGroup($uid, $group)) {
+					return true;
+				}
+			}
+			// Not a member of any of these groups -> no 2FA enforced
+			return false;
+		}
+
+		/**
+		 * If the user is member of an excluded group, 2FA won't be enforced.
+		 */
+		foreach ($state->getExcludedGroups() as $group) {
+			if ($this->groupManager->isInGroup($uid, $group)) {
+				return false;
+			}
+		}
+
+		/**
+		 * No enforced groups configured and user not member of an excluded groups,
+		 * so 2FA is enforced.
+		 */
+		return true;
+	}
+
+
 }