Extract configuration from gateways

This makes it possible to use them in an abstract way and check
if their config is sufficient/valid.

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

19 files changed, 598 insertions, 147 deletions

diff --git a/lib/AppInfo/Application.php b/lib/AppInfo/Application.php
index 2c38aa8..56532e2 100644
--- a/lib/AppInfo/Application.php
+++ b/lib/AppInfo/Application.php
@@ -1,6 +1,6 @@
 <?php
 
-declare(strict_types = 1);
+declare(strict_types=1);
 
 /**
  * @author Christoph Wurst <christoph@winzerhof-wurst.at>
@@ -23,15 +23,7 @@ declare(strict_types = 1);
 
 namespace OCA\TwoFactorGateway\AppInfo;
 
-use Exception;
-use OCA\TwoFactorGateway\Service\Gateway\IGateway;
-use OCA\TwoFactorGateway\Service\Gateway\SMS\PlaySMSGateway;
-use OCA\TwoFactorGateway\Service\Gateway\Signal\Gateway as SignalGateway;
-use OCA\TwoFactorGateway\Service\Gateway\Telegram\Gateway as TelegramGateway;
-use OCA\TwoFactorGateway\Service\Gateway\TestGateway;
-use OCA\TwoFactorGateway\Service\Gateway\SMS\WebSmsGateway;
 use OCP\AppFramework\App;
-use OCP\IConfig;
 
 class Application extends App {
 
@@ -39,30 +31,6 @@ class Application extends App {
 
 	public function __construct(array $urlParams = []) {
 		parent::__construct(self::APP_NAME, $urlParams);
-
-		$container = $this->getContainer();
-
-		/* @var $config IConfig */
-		$config = $container->query(IConfig::class);
-		$provider = $config->getAppValue('twofactor_gateway', 'sms_provider', 'websms.de');
-
-		$container->registerAlias(IGateway::class, $this->getSmsProviderClass($provider));
-	}
-
-	private function getSmsProviderClass(string $name): string {
-		switch ($name) {
-			case 'playsms':
-				return PlaySMSGateway::class;
-			case 'signal':
-				return SignalGateway::class;
-			case 'telegram':
-				return TelegramGateway::class;
-			case 'test':
-				return TestGateway::class;
-			case 'websms.de':
-				return WebSmsGateway::class;
-		}
-		throw new Exception('invalid configuration for twofactor_gateway app');
 	}
 
 }
diff --git a/lib/Exception/ConfigurationException.php b/lib/Exception/ConfigurationException.php
new file mode 100644
index 0000000..cef49f0
--- /dev/null
+++ b/lib/Exception/ConfigurationException.php
@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Exception;
+
+use Exception;
+use Throwable;
+
+class ConfigurationException extends Exception {
+
+	public function __construct(int $code = 0, Throwable $previous = null) {
+		parent::__construct('Invalid gateway/provider configuration set', $code, $previous);
+	}
+
+}
diff --git a/appinfo/app.php b/lib/Exception/InvalidSmsProviderException.php
index 8482273..f6e7e18 100644
--- a/appinfo/app.php
+++ b/lib/Exception/InvalidSmsProviderException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 /**
- * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ * @author Pascal Clémot <pascal.clemot@free.fr>
  *
  * Nextcloud - Two-factor Gateway
  *
@@ -18,6 +20,11 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>
  *
  */
-include_once __DIR__ . '/../vendor/autoload.php';
 
-$app = new OCA\TwoFactorGateway\AppInfo\Application();
+namespace OCA\TwoFactorGateway\Exception;
+
+use Exception;
+
+class InvalidSmsProviderException extends Exception {
+
+}
diff --git a/lib/Provider/SmsProvider.php b/lib/Provider/SmsProvider.php
index 73174c6..12fec2f 100644
--- a/lib/Provider/SmsProvider.php
+++ b/lib/Provider/SmsProvider.php
@@ -26,6 +26,7 @@ namespace OCA\TwoFactorGateway\Provider;
 use OCA\TwoFactorGateway\Exception\SmsTransmissionException;
 use OCA\TwoFactorGateway\PhoneNumberMask;
 use OCA\TwoFactorGateway\Service\Gateway\IGateway;
+use OCA\TwoFactorGateway\Service\Gateway\SMS\SMS;
 use OCA\TwoFactorGateway\Service\StateStorage;
 use OCP\Authentication\TwoFactorAuth\IProvider;
 use OCP\IL10N;
@@ -57,12 +58,12 @@ class SmsProvider implements IProvider {
 	/** @var IL10N */
 	private $l10n;
 
-	public function __construct(IGateway $gateway,
+	public function __construct(SMS $smsGateway,
 								StateStorage $stateStorage,
 								ISession $session,
 								ISecureRandom $secureRandom,
 								IL10N $l10n) {
-		$this->gateway = $gateway;
+		$this->gateway = $smsGateway;
 		$this->stateStorage = $stateStorage;
 		$this->session = $session;
 		$this->secureRandom = $secureRandom;
@@ -89,7 +90,7 @@ class SmsProvider implements IProvider {
 	 * Get the description for selecting the 2FA provider
 	 */
 	public function getDescription(): string {
-		return $this->gateway->getProviderDescription();
+		return $this->l10n->t('Authenticate via SMS');
 	}
 
 	private function getSecret(): string {
diff --git a/lib/Service/Gateway/IGateway.php b/lib/Service/Gateway/IGateway.php
index 588c476..da467c5 100644
--- a/lib/Service/Gateway/IGateway.php
+++ b/lib/Service/Gateway/IGateway.php
@@ -37,19 +37,18 @@ interface IGateway {
 	public function getShortName(): string;
 
 	/**
-	 * Get a gateway-specific description for the gateway 2FA provider,
-	 * e.g. `Authenticate via SMS`.
+	 * Get the gateway-specific configuration
 	 *
-	 * @return string
+	 * @return IGatewayConfig
 	 */
-	public function getProviderDescription(): string;
+	public function getConfig(): IGatewayConfig;
 
 	/**
 	 * @param IUser $user
-	 * @param string $idenfier
+	 * @param string $identifier
 	 * @param string $message
 	 *
 	 * @throws SmsTransmissionException
 	 */
-	public function send(IUser $user, string $idenfier, string $message);
+	public function send(IUser $user, string $identifier, string $message);
 }
diff --git a/lib/Service/Gateway/IGatewayConfig.php b/lib/Service/Gateway/IGatewayConfig.php
new file mode 100644
index 0000000..5b91e47
--- /dev/null
+++ b/lib/Service/Gateway/IGatewayConfig.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway;
+
+interface IGatewayConfig {
+
+	public function isComplete(): bool;
+
+}
\ No newline at end of file
diff --git a/lib/Service/Gateway/SMS/Provider/IProvider.php b/lib/Service/Gateway/SMS/Provider/IProvider.php
new file mode 100644
index 0000000..c6dab88
--- /dev/null
+++ b/lib/Service/Gateway/SMS/Provider/IProvider.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
+
+use OCP\IConfig;
+
+interface IProvider {
+
+	/**
+	 * @param string $identifier
+	 * @param string $message
+	 *
+	 * @throws SmsTransmissionException
+	 */
+	public function send(string $identifier, string $message);
+
+	public function getConfig(): IProviderConfig;
+
+}
\ No newline at end of file
diff --git a/lib/Service/Gateway/SMS/Provider/IProviderConfig.php b/lib/Service/Gateway/SMS/Provider/IProviderConfig.php
new file mode 100644
index 0000000..6feba46
--- /dev/null
+++ b/lib/Service/Gateway/SMS/Provider/IProviderConfig.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
+
+interface IProviderConfig {
+
+	public function isComplete(): bool;
+
+}
diff --git a/lib/Service/Gateway/SMS/Provider/PlaySMS.php b/lib/Service/Gateway/SMS/Provider/PlaySMS.php
new file mode 100644
index 0000000..8c27c6b
--- /dev/null
+++ b/lib/Service/Gateway/SMS/Provider/PlaySMS.php
@@ -0,0 +1,83 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
+
+use Exception;
+use OCA\TwoFactorGateway\Exception\SmsTransmissionException;
+use OCP\Http\Client\IClient;
+use OCP\Http\Client\IClientService;
+use OCP\IConfig;
+
+class PlaySMS implements IProvider {
+
+	const PROVIDER_ID = 'playsms';
+
+	/** @var IClient */
+	private $client;
+
+	/** @var PlaySMSConfig */
+	private $config;
+
+	public function __construct(IClientService $clientService,
+								PlaySMSConfig $config) {
+		$this->client = $clientService->newClient();
+		$this->config = $config;
+	}
+
+	/**
+	 * @param string $identifier
+	 * @param string $message
+	 *
+	 * @throws SmsTransmissionException
+	 */
+	public function send(string $identifier, string $message) {
+		$config = $this->getConfig();
+
+		try {
+			$this->client->get(
+				$config->getUrl(),
+				[
+					'query' => [
+						'app' => 'ws',
+						'u' => $config->getUser(),
+						'h' => $config->getPassword(),
+						'op' => 'pv',
+						'to' => $identifier,
+						'msg' => $message,
+					],
+				]
+			);
+		} catch (Exception $ex) {
+			throw new SmsTransmissionException();
+		}
+	}
+
+	/**
+	 * @return PlaySMSConfig
+	 */
+	public function getConfig(): IProviderConfig {
+		return $this->config;
+	}
+
+}
diff --git a/lib/Service/Gateway/SMS/Provider/PlaySMSConfig.php b/lib/Service/Gateway/SMS/Provider/PlaySMSConfig.php
new file mode 100644
index 0000000..76e32e8
--- /dev/null
+++ b/lib/Service/Gateway/SMS/Provider/PlaySMSConfig.php
@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
+
+use function array_intersect;
+use OCA\TwoFactorGateway\AppInfo\Application;
+use OCA\TwoFactorGateway\Exception\ConfigurationException;
+use OCP\IConfig;
+
+class PlaySMSConfig implements IProviderConfig {
+
+	/** @var IConfig */
+	private $config;
+
+	public function __construct(IConfig $config) {
+		$this->config = $config;
+	}
+
+	private function getOrFail(string $key): string {
+		$val = $this->config->getAppValue(Application::APP_NAME, $key, null);
+		if (is_null($val)) {
+			throw new ConfigurationException();
+		}
+		return $val;
+	}
+
+	public function getUrl(): string {
+		return $this->getOrFail('playsms_url');
+	}
+
+	public function getUser(): string {
+		return $this->getOrFail('playsms_user');
+	}
+
+	public function getPassword(): string {
+		return $this->getOrFail('playsms_password');
+	}
+
+	public function isComplete(): bool {
+		$set = $this->config->getAppKeys(Application::APP_NAME);
+		$expected = [
+			'playsms_url',
+			'playsms_user',
+			'playsms_password',
+		];
+		return count(array_intersect($set, $expected)) === count($expected);
+	}
+}
\ No newline at end of file
diff --git a/lib/Service/Gateway/SMS/Provider/ProviderFactory.php b/lib/Service/Gateway/SMS/Provider/ProviderFactory.php
new file mode 100644
index 0000000..5281061
--- /dev/null
+++ b/lib/Service/Gateway/SMS/Provider/ProviderFactory.php
@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
+
+use OCA\TwoFactorGateway\Exception\InvalidSmsProviderException;
+use OCP\AppFramework\IAppContainer;
+
+class ProviderFactory {
+
+	/** @var IAppContainer */
+	private $container;
+
+	public function __construct(IAppContainer $container) {
+		$this->container = $container;
+	}
+
+	public function getProvider(string $id): IProvider {
+		switch ($id) {
+			case PlaySMS::PROVIDER_ID:
+				return $this->container->query(PlaySMS::class);
+			case WebSms::PROVIDER_ID:
+				return $this->container->query(WebSms::class);
+			default:
+				throw new InvalidSmsProviderException("Provider <$id> does not exist");
+		}
+	}
+
+}
diff --git a/lib/Service/Gateway/SMS/WebSmsGateway.php b/lib/Service/Gateway/SMS/Provider/WebSms.php
index a238a1c..7a2edcc 100644
--- a/lib/Service/Gateway/SMS/WebSmsGateway.php
+++ b/lib/Service/Gateway/SMS/Provider/WebSms.php
@@ -21,46 +21,39 @@ declare(strict_types=1);
  *
  */
 
-namespace OCA\TwoFactorGateway\Service\Gateway\SMS;
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
 
 use Exception;
 use OCA\TwoFactorGateway\Exception\SmsTransmissionException;
-use OCA\TwoFactorGateway\Service\Gateway\IGateway;
 use OCP\Http\Client\IClient;
 use OCP\Http\Client\IClientService;
-use OCP\IConfig;
-use OCP\IL10N;
-use OCP\IUser;
 
-class WebSmsGateway implements IGateway {
+class WebSms implements IProvider {
+
+	const PROVIDER_ID = 'websms';
 
 	/** @var IClient */
 	private $client;
 
-	/** @var IConfig */
+	/** @var WebSmsConfig */
 	private $config;
 
-	/** @var IL10N */
-	private $l10n;
-
 	public function __construct(IClientService $clientService,
-								IConfig $config,
-								IL10N $l10n) {
+								WebSmsConfig $config) {
 		$this->client = $clientService->newClient();
 		$this->config = $config;
-		$this->l10n = $l10n;
 	}
 
 	/**
-	 * @param IUser $user
-	 * @param string $idenfier
+	 * @param string $identifier
 	 * @param string $message
 	 *
 	 * @throws SmsTransmissionException
 	 */
-	public function send(IUser $user, string $idenfier, string $message) {
-		$user = $this->config->getAppValue('twofactor_gateway', 'websms_de_user');
-		$password = $this->config->getAppValue('twofactor_gateway', 'websms_de_password');
+	public function send(string $identifier, string $message) {
+		$config = $this->getConfig();
+		$user = $config->getUser();
+		$password = $config->getPassword();
 		try {
 			$this->client->post('https://api.websms.com/rest/smsmessaging/text', [
 				'headers' => [
@@ -70,7 +63,7 @@ class WebSmsGateway implements IGateway {
 				'json' => [
 					'messageContent' => $message,
 					'test' => false,
-					'recipientAddressList' => [$idenfier],
+					'recipientAddressList' => [$identifier],
 				],
 			]);
 		} catch (Exception $ex) {
@@ -79,19 +72,9 @@ class WebSmsGateway implements IGateway {
 	}
 
 	/**
-	 * Get a short description of this gateway's name so that users know how
-	 * their messages are delivered, e.g. "Telegram"
-	 *
-	 * @return string
-	 */
-	public function getShortName(): string {
-		return 'SMS';
-	}
-
-	/**
-	 * @return string
+	 * @return WebSmsConfig
 	 */
-	public function getProviderDescription(): string {
-		return $this->l10n->t('Authenticate via SMS');
+	public function getConfig(): IProviderConfig {
+		return $this->config;
 	}
 }
diff --git a/lib/Service/Gateway/SMS/Provider/WebSmsConfig.php b/lib/Service/Gateway/SMS/Provider/WebSmsConfig.php
new file mode 100644
index 0000000..93eafd0
--- /dev/null
+++ b/lib/Service/Gateway/SMS/Provider/WebSmsConfig.php
@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ * @author André Fondse <andre@hetnetwerk.org>
+ *
+ * Nextcloud - Two-factor Gateway for Telegram
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS\Provider;
+
+use OCA\TwoFactorGateway\AppInfo\Application;
+use OCA\TwoFactorGateway\Exception\ConfigurationException;
+use OCP\IConfig;
+
+class WebSmsConfig implements IProviderConfig {
+
+	/** @var IConfig */
+	private $config;
+
+	public function __construct(IConfig $config) {
+		$this->config = $config;
+	}
+
+	private function getOrFail(string $key): string {
+		$val = $this->config->getAppValue(Application::APP_NAME, $key, null);
+		if (is_null($val)) {
+			throw new ConfigurationException();
+		}
+		return $val;
+	}
+
+	public function getUser(): string {
+		return $this->getOrFail('websms_de_user');
+	}
+
+	public function getPassword(): string {
+		return $this->getOrFail('websms_de_password');
+	}
+
+	public function isComplete(): bool {
+		$set = $this->config->getAppKeys(Application::APP_NAME);
+		$expected = [
+			'websms_de_user',
+			'websms_de_password',
+		];
+		return count(array_intersect($set, $expected)) === count($expected);
+	}
+
+}
diff --git a/lib/Service/Gateway/SMS/PlaySMSGateway.php b/lib/Service/Gateway/SMS/SMS.php
index c38763e..8a36011 100644
--- a/lib/Service/Gateway/SMS/PlaySMSGateway.php
+++ b/lib/Service/Gateway/SMS/SMS.php
@@ -23,59 +23,29 @@ declare(strict_types=1);
 
 namespace OCA\TwoFactorGateway\Service\Gateway\SMS;
 
-use Exception;
 use OCA\TwoFactorGateway\Exception\SmsTransmissionException;
 use OCA\TwoFactorGateway\Service\Gateway\IGateway;
-use OCP\Http\Client\IClient;
-use OCP\Http\Client\IClientService;
-use OCP\IConfig;
-use OCP\IL10N;
+use OCA\TwoFactorGateway\Service\Gateway\IGatewayConfig;
 use OCP\IUser;
 
-class PlaySMSGateway implements IGateway {
+class SMS implements IGateway {
 
-	/** @var IClient */
-	private $client;
-
-	/** @var IConfig */
+	/** @var SMSConfig */
 	private $config;
 
-	/** @var IL10N */
-	private $l10n;
-
-	public function __construct(IClientService $clientService,
-								IConfig $config,
-								IL10N $l10n) {
-		$this->client = $clientService->newClient();
+	public function __construct(SMSConfig $config) {
 		$this->config = $config;
-		$this->l10n = $l10n;
 	}
 
 	/**
 	 * @param IUser $user
-	 * @param string $idenfier
+	 * @param string $identifier
 	 * @param string $message
 	 *
 	 * @throws SmsTransmissionException
 	 */
-	public function send(IUser $user, string $idenfier, string $message) {
-		$url = $this->config->getAppValue('twofactor_gateway', 'playsms_url');
-		$user = $this->config->getAppValue('twofactor_gateway', 'playsms_user');
-		$password = $this->config->getAppValue('twofactor_gateway', 'playsms_password');
-		try {
-			$this->client->get($url, [
-				'query' => [
-					'app' => 'ws',
-					'u' => $user,
-					'h' => $password,
-					'op' => 'pv',
-					'to' => $idenfier,
-					'msg' => $message,
-				],
-			]);
-		} catch (Exception $ex) {
-			throw new SmsTransmissionException();
-		}
+	public function send(IUser $user, string $identifier, string $message) {
+		$this->config->getProvider()->send($identifier, $message);
 	}
 
 	/**
@@ -89,9 +59,12 @@ class PlaySMSGateway implements IGateway {
 	}
 
 	/**
-	 * @return string
+	 * Get the gateway-specific configuration
+	 *
+	 * @return SMSConfig
 	 */
-	public function getProviderDescription(): string {
-		return $this->l10n->t('Authenticate via SMS');
+	public function getConfig(): IGatewayConfig {
+		return $this->config;
 	}
+
 }
diff --git a/lib/Service/Gateway/SMS/SMSConfig.php b/lib/Service/Gateway/SMS/SMSConfig.php
new file mode 100644
index 0000000..4e3da11
--- /dev/null
+++ b/lib/Service/Gateway/SMS/SMSConfig.php
@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @author Pascal Clémot <pascal.clemot@free.fr>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway\SMS;
+
+use OCA\TwoFactorGateway\AppInfo\Application;
+use OCA\TwoFactorGateway\Exception\ConfigurationException;
+use OCA\TwoFactorGateway\Service\Gateway\IGatewayConfig;
+use OCA\TwoFactorGateway\Service\Gateway\SMS\Provider\IProvider;
+use OCA\TwoFactorGateway\Service\Gateway\SMS\Provider\ProviderFactory;
+use OCP\IConfig;
+
+class SMSConfig implements IGatewayConfig {
+
+	/** @var IConfig */
+	private $config;
+
+	/** @var ProviderFactory */
+	private $providerFactory;
+
+	public function __construct(IConfig $config,
+								ProviderFactory $providerFactory) {
+		$this->config = $config;
+		$this->providerFactory = $providerFactory;
+	}
+
+	public function getProvider(): IProvider {
+		$providerName = $this->config->getAppValue(Application::APP_NAME, 'sms_provider_name', null);
+		if (is_null($providerName)) {
+			throw new ConfigurationException();
+		}
+
+		return $this->providerFactory->getProvider($providerName);
+	}
+
+	public function isComplete(): bool {
+		try {
+			$provider = $this->getProvider();
+			return $provider->getConfig($this->config)->isComplete();
+		} catch (ConfigurationException $ex) {
+			return false;
+		}
+	}
+
+}
\ No newline at end of file
diff --git a/lib/Service/Gateway/Signal/Gateway.php b/lib/Service/Gateway/Signal/Gateway.php
index d4c3f48..f87f37d 100644
--- a/lib/Service/Gateway/Signal/Gateway.php
+++ b/lib/Service/Gateway/Signal/Gateway.php
@@ -26,6 +26,7 @@ namespace OCA\TwoFactorGateway\Service\Gateway\Signal;
 
 use OCA\TwoFactorGateway\Exception\SmsTransmissionException;
 use OCA\TwoFactorGateway\Service\Gateway\IGateway;
+use OCA\TwoFactorGateway\Service\Gateway\IGatewayConfig;
 use OCP\Http\Client\IClientService;
 use OCP\IL10N;
 use OCP\ILogger;
@@ -42,25 +43,20 @@ class Gateway implements IGateway {
 	/** @var ILogger */
 	private $logger;
 
-	/** @var IL10N */
-	private $l10n;
-
 	public function __construct(IClientService $clientService,
-								ILogger $logger,
-								IL10N $l10n) {
+								ILogger $logger) {
 		$this->clientService = $clientService;
 		$this->logger = $logger;
-		$this->l10n = $l10n;
 	}
 
 	/**
 	 * @param IUser $user
-	 * @param string $idenfier
+	 * @param string $identifier
 	 * @param string $message
 	 *
 	 * @throws SmsTransmissionException
 	 */
-	public function send(IUser $user, string $idenfier, string $message) {
+	public function send(IUser $user, string $identifier, string $message) {
 		// TODO: make configurable
 		$endpoint = 'http://localhost:5000';
 
@@ -91,9 +87,12 @@ class Gateway implements IGateway {
 	}
 
 	/**
-	 * @return string
+	 * Get the gateway-specific configuration
+	 *
+	 * @return IGatewayConfig
 	 */
-	public function getProviderDescription(): string {
-		return $this->l10n->t('Authenticate via Signal');
+	public function getConfig(): IGatewayConfig {
+		// TODO: Implement getConfig() method.
 	}
+
 }
diff --git a/lib/Service/Gateway/State.php b/lib/Service/Gateway/State.php
new file mode 100644
index 0000000..00c4c22
--- /dev/null
+++ b/lib/Service/Gateway/State.php
@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Nextcloud - Two-factor Gateway
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\TwoFactorGateway\Service\Gateway;
+
+
+class State {
+
+	const DISABLED = 0;
+	const VERIFYING = 1;
+	const ENABLED = 2;
+
+	/** @var int */
+	private $state;
+
+	private function __construct(int $state) {
+		$this->state = $state;
+	}
+
+	public static function disabled(): State {
+		return new self(self::DISABLED);
+	}
+
+	public static function verifying(): State {
+		return new self(self::VERIFYING);
+	}
+
+	public static function enabled(): State {
+		return new self(self::ENABLED);
+	}
+
+	public function isDisabled(): bool {
+		return $this->state === self::DISABLED;
+	}
+
+	public function isVerifying(): bool {
+		return $this->state === self::DISABLED;
+	}
+
+	public function isEnabled(): bool {
+		return $this->state === self::DISABLED;
+	}
+
+}
diff --git a/lib/Service/Gateway/Telegram/Gateway.php b/lib/Service/Gateway/Telegram/Gateway.php
index 444eaaf..0a6b326 100644
--- a/lib/Service/Gateway/Telegram/Gateway.php
+++ b/lib/Service/Gateway/Telegram/Gateway.php
@@ -27,6 +27,7 @@ namespace OCA\TwoFactorGateway\Service\Gateway\Telegram;
 use Exception;
 use OCA\TwoFactorGateway\Exception\SmsTransmissionException;
 use OCA\TwoFactorGateway\Service\Gateway\IGateway;
+use OCA\TwoFactorGateway\Service\Gateway\IGatewayConfig;
 use OCP\Http\Client\IClient;
 use OCP\Http\Client\IClientService;
 use OCP\IConfig;
@@ -43,25 +44,20 @@ class Gateway implements IGateway {
 	/** @var IConfig */
 	private $config;
 
-	/** @var IL10N */
-	private $l10n;
-
 	public function __construct(IClientService $clientService,
-								IConfig $config,
-								IL10N $l10n) {
+								IConfig $config) {
 		$this->client = $clientService->newClient();
 		$this->config = $config;
-		$this->l10n = $l10n;
 	}
 
 	/**
 	 * @param IUser $user
-	 * @param string $idenfier
+	 * @param string $identifier
 	 * @param string $message
 	 *
-	 * @throws \Telegram\Bot\Exceptions\TelegramSDKException
+	 * @throws SmsTransmissionException
 	 */
-	public function send(IUser $user, string $idenfier, string $message) {
+	public function send(IUser $user, string $identifier, string $message) {
 		$token = $this->config->getAppValue('twofactor_gateway', 'telegram_bot_token', null);
 		// TODO: token missing handling
 
@@ -108,9 +104,11 @@ class Gateway implements IGateway {
 	}
 
 	/**
-	 * @return string
+	 * Get the gateway-specific configuration
+	 *
+	 * @return IGatewayConfig
 	 */
-	public function getProviderDescription(): string {
-		return $this->l10n->t('Authenticate via Telegram');
+	public function getConfig(): IGatewayConfig {
+		// TODO: Implement getConfig() method.
 	}
 }
diff --git a/lib/Service/StateStorage.php b/lib/Service/StateStorage.php
index e53f637..75e3f0f 100644
--- a/lib/Service/StateStorage.php
+++ b/lib/Service/StateStorage.php
@@ -37,13 +37,8 @@ class StateStorage {
 	/** @var IConfig */
 	private $config;
 
-	/** @var IGateway */
-	private $gateway;
-
-	public function __construct(IConfig $config,
-								IGateway $gateway) {
+	public function __construct(IConfig $config) {
 		$this->config = $config;
-		$this->gateway = $gateway;
 	}
 
 	public function get(IUser $user): State {
@@ -62,7 +57,7 @@ class StateStorage {
 		return new State(
 			$user,
 			$state,
-			$this->gateway->getShortName(),
+			'', // TODO: fix
 			$identifier,
 			$verificationCode
 		);