Always allow users to login via email link, even if an install does not use passwords

Summary:
Depends on D20099. Ref T13244. See PHI774. When password auth is enabled, we support a standard email-based account recovery mechanism with "Forgot password?".

When password auth is not enabled, we disable the self-serve version of this mechanism. You can still get email account login links via "Send Welcome Mail" or "bin/auth recover".

There's no real technical, product, or security reason not to let everyone do email login all the time. On the technical front, these links already work and are used in other contexts. On the product front, we just need to tweak a couple of strings.

On the security front, there's some argument that this mechanism provides more overall surface area for an attacker, but if we find that argument compelling we should probably provide a way to disable the self-serve pathway in all cases, rather than coupling it to which providers are enabled.

Also, inch toward having things iterate over configurations (saved database objects) instead of providers (abstract implementations) so we can some day live in a world where we support multiple configurations of the same provider type (T6703).

Test Plan:
  - With password auth enabled, reset password.
  - Without password auth enabled, did an email login recovery.

{F6184910}

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T13244

Differential Revision: https://secure.phabricator.com/D20100

src/applications/auth/controller/PhabricatorAuthStartController.php

@@ -75,6 +75,11 @@ final class PhabricatorAuthStartController
       }
     }
 
+    $configs = array();
+    foreach ($providers as $provider) {
+      $configs[] = $provider->getProviderConfig();
+    }
+
     if (!$providers) {
       if ($this->isFirstTimeSetup()) {
         // If this is a fresh install, let the user register their admin
@@ -179,6 +184,8 @@ final class PhabricatorAuthStartController
 
     $custom_message = $this->newCustomStartMessage();
 
+    $email_login = $this->newEmailLoginView($configs);
+
     $crumbs = $this->buildApplicationCrumbs();
     $crumbs->addTextCrumb(pht('Login'));
     $crumbs->setBorder(true);
@@ -188,6 +195,7 @@ final class PhabricatorAuthStartController
       $invite_message,
       $custom_message,
       $out,
+      $email_login,
     );
 
     return $this->newPage()
@@ -311,4 +319,43 @@ final class PhabricatorAuthStartController
       $remarkup_view);
   }
 
+  private function newEmailLoginView(array $configs) {
+    assert_instances_of($configs, 'PhabricatorAuthProviderConfig');
+
+    // Check if password auth is enabled. If it is, the password login form
+    // renders a "Forgot password?" link, so we don't need to provide a
+    // supplemental link.
+
+    $has_password = false;
+    foreach ($configs as $config) {
+      $provider = $config->getProvider();
+      if ($provider instanceof PhabricatorPasswordAuthProvider) {
+        $has_password = true;
+      }
+    }
+
+    if ($has_password) {
+      return null;
+    }
+
+    $view = array(
+      pht('Trouble logging in?'),
+      ' ',
+      phutil_tag(
+        'a',
+        array(
+          'href' => '/login/email/',
+        ),
+        pht('Send a login link to your email address.')),
+    );
+
+    return phutil_tag(
+      'div',
+      array(
+        'class' => 'auth-custom-message',
+      ),
+      $view);
+  }
+
+
 }

src/applications/auth/controller/PhabricatorEmailLoginController.php

@@ -8,17 +8,13 @@ final class PhabricatorEmailLoginController
   }
 
   public function handleRequest(AphrontRequest $request) {
-
-    if (!PhabricatorPasswordAuthProvider::getPasswordProvider()) {
-      return new Aphront400Response();
-    }
+    $viewer = $this->getViewer();
 
     $e_email = true;
     $e_captcha = true;
     $errors = array();
 
-    $is_serious = PhabricatorEnv::getEnvConfig('phabricator.serious-business');
-
+    $v_email = $request->getStr('email');
     if ($request->isFormPost()) {
       $e_email = null;
       $e_captcha = pht('Again');
@@ -29,8 +25,7 @@ final class PhabricatorEmailLoginController
         $e_captcha = pht('Invalid');
       }
 
-      $email = $request->getStr('email');
-      if (!strlen($email)) {
+      if (!strlen($v_email)) {
        $errors[] = pht('You must provide an email address.');
        $e_email = pht('Required');
       }
@@ -42,7 +37,7 @@ final class PhabricatorEmailLoginController
 
         $target_email = id(new PhabricatorUserEmail())->loadOneWhere(
           'address = %s',
-          $email);
+          $v_email);
 
         $target_user = null;
         if ($target_email) {
@@ -81,33 +76,10 @@ final class PhabricatorEmailLoginController
         }
 
         if (!$errors) {
-          $engine = new PhabricatorAuthSessionEngine();
-          $uri = $engine->getOneTimeLoginURI(
-            $target_user,
-            null,
-            PhabricatorAuthSessionEngine::ONETIME_RESET);
-
-          if ($is_serious) {
-            $body = pht(
-              "You can use this link to reset your Phabricator password:".
-              "\n\n  %s\n",
-              $uri);
-          } else {
-            $body = pht(
-              "Condolences on forgetting your password. You can use this ".
-              "link to reset it:\n\n".
-              "  %s\n\n".
-              "After you set a new password, consider writing it down on a ".
-              "sticky note and attaching it to your monitor so you don't ".
-              "forget again! Choosing a very short, easy-to-remember password ".
-              "like \"cat\" or \"1234\" might also help.\n\n".
-              "Best Wishes,\nPhabricator\n",
-              $uri);
-
-          }
+          $body = $this->newAccountLoginMailBody($target_user);
 
           $mail = id(new PhabricatorMetaMTAMail())
-            ->setSubject(pht('[Phabricator] Password Reset'))
+            ->setSubject(pht('[Phabricator] Account Login Link'))
             ->setForceDelivery(true)
             ->addRawTos(array($target_email->getAddress()))
             ->setBody($body)
@@ -123,44 +95,90 @@ final class PhabricatorEmailLoginController
       }
     }
 
-    $error_view = null;
-    if ($errors) {
-      $error_view = new PHUIInfoView();
-      $error_view->setErrors($errors);
+    $form = id(new AphrontFormView())
+      ->setViewer($viewer);
+
+    if ($this->isPasswordAuthEnabled()) {
+      $form->appendRemarkupInstructions(
+        pht(
+          'To reset your password, provide your email address. An email '.
+          'with a login link will be sent to you.'));
+    } else {
+      $form->appendRemarkupInstructions(
+        pht(
+          'To access your account, provide your email address. An email '.
+          'with a login link will be sent to you.'));
     }
 
-    $email_auth = new PHUIFormLayoutView();
-    $email_auth->appendChild($error_view);
-    $email_auth
-      ->setUser($request->getUser())
-      ->setFullWidth(true)
-      ->appendChild(
+    $form
+      ->appendControl(
         id(new AphrontFormTextControl())
-          ->setLabel(pht('Email'))
+          ->setLabel(pht('Email Address'))
           ->setName('email')
-          ->setValue($request->getStr('email'))
+          ->setValue($v_email)
           ->setError($e_email))
-      ->appendChild(
+      ->appendControl(
         id(new AphrontFormRecaptchaControl())
           ->setLabel(pht('Captcha'))
           ->setError($e_captcha));
 
-    $crumbs = $this->buildApplicationCrumbs();
-    $crumbs->addTextCrumb(pht('Reset Password'));
-    $crumbs->setBorder(true);
-
-    $dialog = new AphrontDialogView();
-    $dialog->setUser($request->getUser());
-    $dialog->setTitle(pht('Forgot Password / Email Login'));
-    $dialog->appendChild($email_auth);
-    $dialog->addSubmitButton(pht('Send Email'));
-    $dialog->setSubmitURI('/login/email/');
-
-    return $this->newPage()
-      ->setTitle(pht('Forgot Password'))
-      ->setCrumbs($crumbs)
-      ->appendChild($dialog);
+    if ($this->isPasswordAuthEnabled()) {
+      $title = pht('Password Reset');
+    } else {
+      $title = pht('Email Login');
+    }
 
+    return $this->newDialog()
+      ->setTitle($title)
+      ->setErrors($errors)
+      ->setWidth(AphrontDialogView::WIDTH_FORM)
+      ->appendForm($form)
+      ->addCancelButton('/auth/start/')
+      ->addSubmitButton(pht('Send Email'));
   }
 
+  private function newAccountLoginMailBody(PhabricatorUser $user) {
+    $engine = new PhabricatorAuthSessionEngine();
+    $uri = $engine->getOneTimeLoginURI(
+      $user,
+      null,
+      PhabricatorAuthSessionEngine::ONETIME_RESET);
+
+    $is_serious = PhabricatorEnv::getEnvConfig('phabricator.serious-business');
+    $have_passwords = $this->isPasswordAuthEnabled();
+
+    if ($have_passwords) {
+      if ($is_serious) {
+        $body = pht(
+          "You can use this link to reset your Phabricator password:".
+          "\n\n  %s\n",
+          $uri);
+      } else {
+        $body = pht(
+          "Condolences on forgetting your password. You can use this ".
+          "link to reset it:\n\n".
+          "  %s\n\n".
+          "After you set a new password, consider writing it down on a ".
+          "sticky note and attaching it to your monitor so you don't ".
+          "forget again! Choosing a very short, easy-to-remember password ".
+          "like \"cat\" or \"1234\" might also help.\n\n".
+          "Best Wishes,\nPhabricator\n",
+          $uri);
+
+      }
+    } else {
+      $body = pht(
+        "You can use this login link to regain access to your Phabricator ".
+        "account:".
+        "\n\n".
+        "  %s\n",
+        $uri);
+    }
+
+    return $body;
+  }
+
+  private function isPasswordAuthEnabled() {
+    return (bool)PhabricatorPasswordAuthProvider::getPasswordProvider();
+  }
 }