Add "High Security" mode to support multi-factor auth

Summary:
Ref T4398. This is roughly a "sudo" mode, like GitHub has for accessing SSH keys, or Facebook has for managing credit cards. GitHub actually calls theirs "sudo" mode, but I think that's too technical for big parts of our audience. I've gone with "high security mode".

This doesn't actually get exposed in the UI yet (and we don't have any meaningful auth factors to prompt the user for) but the workflow works overall. I'll go through it in a comment, since I need to arrange some screenshots.

Test Plan: See guided walkthrough.

Reviewers: chad, btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T4398

Differential Revision: https://secure.phabricator.com/D8851

resources/sql/autopatches/20140423.session.1.hisec.sql

@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_user.phabricator_session
+  ADD highSecurityUntil INT UNSIGNED;

src/__phutil_library_map__.php

@@ -1206,7 +1206,10 @@ phutil_register_library_map(array(
     'PhabricatorAuthController' => 'applications/auth/controller/PhabricatorAuthController.php',
     'PhabricatorAuthDAO' => 'applications/auth/storage/PhabricatorAuthDAO.php',
     'PhabricatorAuthDisableController' => 'applications/auth/controller/config/PhabricatorAuthDisableController.php',
+    'PhabricatorAuthDowngradeSessionController' => 'applications/auth/controller/PhabricatorAuthDowngradeSessionController.php',
     'PhabricatorAuthEditController' => 'applications/auth/controller/config/PhabricatorAuthEditController.php',
+    'PhabricatorAuthHighSecurityRequiredException' => 'applications/auth/exception/PhabricatorAuthHighSecurityRequiredException.php',
+    'PhabricatorAuthHighSecurityToken' => 'applications/auth/data/PhabricatorAuthHighSecurityToken.php',
     'PhabricatorAuthLinkController' => 'applications/auth/controller/PhabricatorAuthLinkController.php',
     'PhabricatorAuthListController' => 'applications/auth/controller/config/PhabricatorAuthListController.php',
     'PhabricatorAuthLoginController' => 'applications/auth/controller/PhabricatorAuthLoginController.php',
@@ -3947,7 +3950,9 @@ phutil_register_library_map(array(
     'PhabricatorAuthController' => 'PhabricatorController',
     'PhabricatorAuthDAO' => 'PhabricatorLiskDAO',
     'PhabricatorAuthDisableController' => 'PhabricatorAuthProviderConfigController',
+    'PhabricatorAuthDowngradeSessionController' => 'PhabricatorAuthController',
     'PhabricatorAuthEditController' => 'PhabricatorAuthProviderConfigController',
+    'PhabricatorAuthHighSecurityRequiredException' => 'Exception',
     'PhabricatorAuthLinkController' => 'PhabricatorAuthController',
     'PhabricatorAuthListController' => 'PhabricatorAuthProviderConfigController',
     'PhabricatorAuthLoginController' => 'PhabricatorAuthController',

src/aphront/AphrontRequest.php

@@ -18,6 +18,7 @@ final class AphrontRequest {
   const TYPE_WORKFLOW = '__wflow__';
   const TYPE_CONTINUE = '__continue__';
   const TYPE_PREVIEW = '__preview__';
+  const TYPE_HISEC = '__hisec__';
 
   private $host;
   private $path;
@@ -263,6 +264,7 @@ final class AphrontRequest {
 
   final public function isFormPost() {
     $post = $this->getExists(self::TYPE_FORM) &&
+            !$this->getExists(self::TYPE_HISEC) &&
             $this->isHTTPPost();
 
     if (!$post) {

src/aphront/configuration/AphrontDefaultApplicationConfiguration.php

@@ -123,6 +123,49 @@ class AphrontDefaultApplicationConfiguration
       return $response;
     }
 
+    if ($ex instanceof PhabricatorAuthHighSecurityRequiredException) {
+
+      $form = id(new PhabricatorAuthSessionEngine())->renderHighSecurityForm(
+        $user,
+        $request);
+
+      $dialog = id(new AphrontDialogView())
+        ->setUser($user)
+        ->setTitle(pht('Entering High Security'))
+        ->setShortTitle(pht('Security Checkpoint'))
+        ->setWidth(AphrontDialogView::WIDTH_FORM)
+        ->addHiddenInput(AphrontRequest::TYPE_HISEC, true)
+        ->setErrors(
+          array(
+            pht(
+              'You are taking an action which requires you to enter '.
+              'high security.'),
+          ))
+        ->appendParagraph(
+          pht(
+            'High security mode helps protect your account from security '.
+            'threats, like session theft or someone messing with your stuff '.
+            'while you\'re grabbing a coffee. To enter high security mode, '.
+            'confirm your credentials.'))
+        ->appendChild($form->buildLayoutView())
+        ->appendParagraph(
+          pht(
+            'Your account will remain in high security mode for a short '.
+            'period of time. When you are finished taking sensitive '.
+            'actions, you should leave high security.'))
+        ->setSubmitURI($request->getPath())
+        ->addCancelButton($ex->getCancelURI())
+        ->addSubmitButton(pht('Enter High Security'));
+
+      foreach ($request->getPassthroughRequestParameters() as $key => $value) {
+        $dialog->addHiddenInput($key, $value);
+      }
+
+      $response = new AphrontDialogResponse();
+      $response->setDialog($dialog);
+      return $response;
+    }
+
     if ($ex instanceof PhabricatorPolicyException) {
 
       if (!$user->isLoggedIn()) {

src/applications/auth/application/PhabricatorApplicationAuth.php

@@ -88,6 +88,8 @@ final class PhabricatorApplicationAuth extends PhabricatorApplication {
           => 'PhabricatorAuthConfirmLinkController',
         'session/terminate/(?P<id>[^/]+)/'
           => 'PhabricatorAuthTerminateSessionController',
+        'session/downgrade/'
+          => 'PhabricatorAuthDowngradeSessionController',
       ),
 
       '/oauth/(?P<provider>\w+)/login/'

src/applications/auth/controller/PhabricatorAuthDowngradeSessionController.php

@@ -0,0 +1,52 @@
+<?php
+
+final class PhabricatorAuthDowngradeSessionController
+  extends PhabricatorAuthController {
+
+  public function processRequest() {
+    $request = $this->getRequest();
+    $viewer = $request->getUser();
+
+    $panel_uri = '/settings/panel/sessions/';
+
+    $session = $viewer->getSession();
+    if ($session->getHighSecurityUntil() < time()) {
+      return $this->newDialog()
+        ->setTitle(pht('Normal Security Restored'))
+        ->appendParagraph(
+          pht('Your session is no longer in high security.'))
+        ->addCancelButton($panel_uri, pht('Continue'));
+    }
+
+    if ($request->isFormPost()) {
+
+      queryfx(
+        $session->establishConnection('w'),
+        'UPDATE %T SET highSecurityUntil = NULL WHERE id = %d',
+        $session->getTableName(),
+        $session->getID());
+
+      return id(new AphrontRedirectResponse())
+        ->setURI($this->getApplicationURI('session/downgrade/'));
+    }
+
+    return $this->newDialog()
+      ->setTitle(pht('Leaving High Security'))
+      ->appendParagraph(
+        pht(
+          'Leave high security and return your session to normal '.
+          'security levels?'))
+      ->appendParagraph(
+        pht(
+          'If you leave high security, you will need to authenticate '.
+          'again the next time you try to take a high security action.'))
+      ->appendParagraph(
+        pht(
+          'On the plus side, that purple notification bubble will '.
+          'disappear.'))
+      ->addSubmitButton(pht('Leave High Security'))
+      ->addCancelButton($panel_uri, pht('Stay in High Security'));
+  }
+
+
+}

src/applications/auth/data/PhabricatorAuthHighSecurityToken.php

@@ -0,0 +1,5 @@
+<?php
+
+final class PhabricatorAuthHighSecurityToken {
+
+}

src/applications/auth/engine/PhabricatorAuthSessionEngine.php

@@ -1,5 +1,8 @@
 <?php
 
+/**
+ * @task hisec High Security Mode
+ */
 final class PhabricatorAuthSessionEngine extends Phobject {
 
   /**
@@ -78,28 +81,43 @@ final class PhabricatorAuthSessionEngine extends Phobject {
     $session_table = new PhabricatorAuthSession();
     $user_table = new PhabricatorUser();
     $conn_r = $session_table->establishConnection('r');
+    $session_key = PhabricatorHash::digest($session_token);
 
     // NOTE: We're being clever here because this happens on every page load,
-    // and by joining we can save a query.
+    // and by joining we can save a query. This might be getting too clever
+    // for its own good, though...
 
     $info = queryfx_one(
       $conn_r,
-      'SELECT s.sessionExpires AS _sessionExpires, s.id AS _sessionID, u.*
+      'SELECT
+          s.id AS s_id,
+          s.sessionExpires AS s_sessionExpires,
+          s.sessionStart AS s_sessionStart,
+          s.highSecurityUntil AS s_highSecurityUntil,
+          u.*
         FROM %T u JOIN %T s ON u.phid = s.userPHID
         AND s.type = %s AND s.sessionKey = %s',
       $user_table->getTableName(),
       $session_table->getTableName(),
       $session_type,
-      PhabricatorHash::digest($session_token));
+      $session_key);
 
     if (!$info) {
       return null;
     }
 
-    $expires = $info['_sessionExpires'];
-    $id = $info['_sessionID'];
-    unset($info['_sessionExpires']);
-    unset($info['_sessionID']);
+    $session_dict = array(
+      'userPHID' => $info['phid'],
+      'sessionKey' => $session_key,
+      'type' => $session_type,
+    );
+    foreach ($info as $key => $value) {
+      if (strncmp($key, 's_', 2) === 0) {
+        unset($info[$key]);
+        $session_dict[substr($key, 2)] = $value;
+      }
+    }
+    $session = id(new PhabricatorAuthSession())->loadFromArray($session_dict);
 
     $ttl = PhabricatorAuthSession::getSessionTypeTTL($session_type);
 
@@ -107,19 +125,21 @@ final class PhabricatorAuthSessionEngine extends Phobject {
     // TTL back up to the full duration. The idea here is that sessions are
     // good forever if used regularly, but get GC'd when they fall out of use.
 
-    if (time() + (0.80 * $ttl) > $expires) {
+    if (time() + (0.80 * $ttl) > $session->getSessionExpires()) {
       $unguarded = AphrontWriteGuard::beginScopedUnguardedWrites();
         $conn_w = $session_table->establishConnection('w');
         queryfx(
           $conn_w,
           'UPDATE %T SET sessionExpires = UNIX_TIMESTAMP() + %d WHERE id = %d',
-          $session_table->getTableName(),
+          $session->getTableName(),
           $ttl,
-          $id);
+          $session->getID());
       unset($unguarded);
     }
 
-    return $user_table->loadFromArray($info);
+    $user = $user_table->loadFromArray($info);
+    $user->attachSession($session);
+    return $user;
   }
 
 
@@ -182,4 +202,104 @@ final class PhabricatorAuthSessionEngine extends Phobject {
     return $session_key;
   }
 
+
+  /**
+   * Require high security, or prompt the user to enter high security.
+   *
+   * If the user's session is in high security, this method will return a
+   * token. Otherwise, it will throw an exception which will eventually
+   * be converted into a multi-factor authentication workflow.
+   *
+   * @param PhabricatorUser User whose session needs to be in high security.
+   * @param AphrontReqeust  Current request.
+   * @param string          URI to return the user to if they cancel.
+   * @return PhabricatorAuthHighSecurityToken Security token.
+   */
+  public function requireHighSecuritySession(
+    PhabricatorUser $viewer,
+    AphrontRequest $request,
+    $cancel_uri) {
+
+    if (!$viewer->hasSession()) {
+      throw new Exception(
+        pht('Requiring a high-security session from a user with no session!'));
+    }
+
+    $session = $viewer->getSession();
+
+    $token = $this->issueHighSecurityToken($session);
+    if ($token) {
+      return $token;
+    }
+
+    if ($request->isHTTPPost()) {
+      $request->validateCSRF();
+      if ($request->getExists(AphrontRequest::TYPE_HISEC)) {
+
+        // TODO: Actually verify that the user provided some multi-factor
+        // auth credentials here. For now, we just let you enter high
+        // security.
+
+        $until = time() + phutil_units('15 minutes in seconds');
+        $session->setHighSecurityUntil($until);
+
+        queryfx(
+          $session->establishConnection('w'),
+          'UPDATE %T SET highSecurityUntil = %d WHERE id = %d',
+          $session->getTableName(),
+          $until,
+          $session->getID());
+      }
+    }
+
+    $token = $this->issueHighSecurityToken($session);
+    if ($token) {
+      return $token;
+    }
+
+    throw id(new PhabricatorAuthHighSecurityRequiredException())
+      ->setCancelURI($cancel_uri);
+  }
+
+
+  /**
+   * Issue a high security token for a session, if authorized.
+   *
+   * @param PhabricatorAuthSession Session to issue a token for.
+   * @return PhabricatorAuthHighSecurityToken|null Token, if authorized.
+   */
+  private function issueHighSecurityToken(PhabricatorAuthSession $session) {
+    $until = $session->getHighSecurityUntil();
+    if ($until > time()) {
+      return new PhabricatorAuthHighSecurityToken();
+    }
+    return null;
+  }
+
+
+  /**
+   * Render a form for providing relevant multi-factor credentials.
+   *
+   * @param   PhabricatorUser Viewing user.
+   * @param   AphrontRequest  Current request.
+   * @return  AphrontFormView Renderable form.
+   */
+  public function renderHighSecurityForm(
+    PhabricatorUser $viewer,
+    AphrontRequest $request) {
+
+    // TODO: This is stubbed.
+
+    $form = id(new AphrontFormView())
+      ->setUser($viewer)
+      ->appendRemarkupInstructions('')
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setLabel(pht('Secret Stuff')))
+      ->appendRemarkupInstructions('');
+
+    return $form;
+  }
+
+
 }

src/applications/auth/exception/PhabricatorAuthHighSecurityRequiredException.php

@@ -0,0 +1,16 @@
+<?php
+
+final class PhabricatorAuthHighSecurityRequiredException extends Exception {
+
+  private $cancelURI;
+
+  public function setCancelURI($cancel_uri) {
+    $this->cancelURI = $cancel_uri;
+    return $this;
+  }
+
+  public function getCancelURI() {
+    return $this->cancelURI;
+  }
+
+}

src/applications/auth/storage/PhabricatorAuthSession.php

@@ -11,6 +11,7 @@ final class PhabricatorAuthSession extends PhabricatorAuthDAO
   protected $sessionKey;
   protected $sessionStart;
   protected $sessionExpires;
+  protected $highSecurityUntil;
 
   private $identityObject = self::ATTACHABLE;
 

src/applications/people/storage/PhabricatorUser.php

@@ -42,6 +42,7 @@ final class PhabricatorUser
   private $customFields = self::ATTACHABLE;
 
   private $alternateCSRFString = self::ATTACHABLE;
+  private $session = self::ATTACHABLE;
 
   protected function readField($field) {
     switch ($field) {
@@ -178,6 +179,19 @@ final class PhabricatorUser
     return $result;
   }
 
+  public function attachSession(PhabricatorAuthSession $session) {
+    $this->session = $session;
+    return $this;
+  }
+
+  public function getSession() {
+    return $this->assertAttached($this->session);
+  }
+
+  public function hasSession() {
+    return ($this->session !== self::ATTACHABLE);
+  }
+
   private function generateConduitCertificate() {
     return Filesystem::readRandomCharacters(255);
   }

src/applications/settings/panel/PhabricatorSettingsPanelSSHKeys.php

@@ -38,6 +38,18 @@ final class PhabricatorSettingsPanelSSHKeys
       return $this->renderKeyListView($request);
     }
 
+    /*
+
+    NOTE: Uncomment this to test hisec.
+    TOOD: Implement this fully once hisec does something useful.
+
+    $token = id(new PhabricatorAuthSessionEngine())->requireHighSecuritySession(
+      $viewer,
+      $request,
+      '/settings/panel/ssh/');
+
+    */
+
     $id = nonempty($edit, $delete);
 
     if ($id && is_numeric($id)) {

src/applications/settings/panel/PhabricatorSettingsPanelSessions.php

@@ -66,10 +66,15 @@ final class PhabricatorSettingsPanelSessions
           pht('Terminate'));
       }
 
+      $hisec = ($session->getHighSecurityUntil() - time());
+
       $rows[] = array(
         $handles[$session->getUserPHID()]->renderLink(),
         substr($session->getSessionKey(), 0, 6),
         $session->getType(),
+        ($hisec > 0)
+          ? phabricator_format_relative_time($hisec)
+          : null,
         phabricator_datetime($session->getSessionStart(), $viewer),
         phabricator_date($session->getSessionExpires(), $viewer),
         $button,
@@ -84,6 +89,7 @@ final class PhabricatorSettingsPanelSessions
         pht('Identity'),
         pht('Session'),
         pht('Type'),
+        pht('HiSec'),
         pht('Created'),
         pht('Expires'),
         pht(''),
@@ -95,6 +101,7 @@ final class PhabricatorSettingsPanelSessions
         '',
         'right',
         'right',
+        'right',
         'action',
       ));
 
@@ -113,6 +120,20 @@ final class PhabricatorSettingsPanelSessions
       ->setHeader(pht('Active Login Sessions'))
       ->addActionLink($terminate_button);
 
+    $hisec = ($viewer->getSession()->getHighSecurityUntil() - time());
+    if ($hisec > 0) {
+      $hisec_icon = id(new PHUIIconView())
+        ->setSpriteSheet(PHUIIconView::SPRITE_ICONS)
+        ->setSpriteIcon('lock');
+      $hisec_button = id(new PHUIButtonView())
+        ->setText(pht('Leave High Security'))
+        ->setHref('/auth/session/downgrade/')
+        ->setTag('a')
+        ->setWorkflow(true)
+        ->setIcon($hisec_icon);
+      $header->addActionLink($hisec_button);
+    }
+
     $panel = id(new PHUIObjectBoxView())
       ->setHeader($header)
       ->appendChild($table);

src/view/page/PhabricatorStandardPageView.php

@@ -168,6 +168,22 @@ final class PhabricatorStandardPageView extends PhabricatorBarePageView {
 
     Javelin::initBehavior('device');
 
+    if ($user->hasSession()) {
+      $hisec = ($user->getSession()->getHighSecurityUntil() - time());
+      if ($hisec > 0) {
+        $remaining_time = phabricator_format_relative_time($hisec);
+        Javelin::initBehavior(
+          'high-security-warning',
+          array(
+            'uri' => '/auth/session/downgrade/',
+            'message' => pht(
+              'Your session is in high security mode. When you '.
+              'finish using it, click here to leave.',
+              $remaining_time),
+          ));
+      }
+    }
+
     if ($console) {
       require_celerity_resource('aphront-dark-console-css');
 

webroot/rsrc/css/aphront/notification.css

@@ -47,6 +47,11 @@
   border: 1px solid {$red};
 }
 
+.jx-notification-security {
+  background: {$lightviolet};
+  border: 1px solid {$violet};
+}
+
 .jx-notification-container .phabricator-notification {
   padding: 0;
 }

webroot/rsrc/js/core/behavior-high-security-warning.js

@@ -0,0 +1,19 @@
+/**
+ * @provides javelin-behavior-high-security-warning
+ * @requires javelin-behavior
+ *           javelin-uri
+ *           phabricator-notification
+ */
+
+JX.behavior('high-security-warning', function(config) {
+
+  var n = new JX.Notification()
+    .setContent(config.message)
+    .setDuration(0)
+    .alterClassName('jx-notification-security', true);
+
+  n.listen('activate', function() { JX.$U(config.uri).go(); });
+
+  n.show();
+
+});