Implement new auth login flow and login validation controller

Summary:
Ref T1536. None of this code is reachable.

Implements new-auth login (so you can actually login) and login validation (which checks that cookies were set correctly).

Test Plan: Manually enabled FB auth, went through the auth flow to login/logout. Manually hit most of the validation errors.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T1536

Differential Revision: https://secure.phabricator.com/D6162

src/__phutil_library_map__.php

@@ -821,6 +821,7 @@ phutil_register_library_map(array(
     'PhabricatorAuthProviderOAuthFacebook' => 'applications/auth/provider/PhabricatorAuthProviderOAuthFacebook.php',
     'PhabricatorAuthRegisterController' => 'applications/auth/controller/PhabricatorAuthRegisterController.php',
     'PhabricatorAuthStartController' => 'applications/auth/controller/PhabricatorAuthStartController.php',
+    'PhabricatorAuthValidateController' => 'applications/auth/controller/PhabricatorAuthValidateController.php',
     'PhabricatorAuthenticationConfigOptions' => 'applications/config/option/PhabricatorAuthenticationConfigOptions.php',
     'PhabricatorBarePageExample' => 'applications/uiexample/examples/PhabricatorBarePageExample.php',
     'PhabricatorBarePageView' => 'view/page/PhabricatorBarePageView.php',
@@ -2679,6 +2680,7 @@ phutil_register_library_map(array(
     'PhabricatorAuthProviderOAuthFacebook' => 'PhabricatorAuthProviderOAuth',
     'PhabricatorAuthRegisterController' => 'PhabricatorAuthController',
     'PhabricatorAuthStartController' => 'PhabricatorAuthController',
+    'PhabricatorAuthValidateController' => 'PhabricatorAuthController',
     'PhabricatorAuthenticationConfigOptions' => 'PhabricatorApplicationConfigOptions',
     'PhabricatorBarePageExample' => 'PhabricatorUIExample',
     'PhabricatorBarePageView' => 'AphrontPageView',

src/applications/auth/application/PhabricatorApplicationAuth.php

@@ -39,6 +39,7 @@ final class PhabricatorApplicationAuth extends PhabricatorApplication {
         'login/(?P<pkey>[^/]+)/' => 'PhabricatorAuthLoginController',
         'register/(?P<akey>[^/]+)/' => 'PhabricatorAuthRegisterController',
         'start/' => 'PhabricatorAuthStartController',
+        'validate/' => 'PhabricatorAuthValidateController',
       ),
     );
   }

src/applications/auth/controller/PhabricatorAuthLoginController.php

@@ -80,7 +80,8 @@ final class PhabricatorAuthLoginController
             pht(
               'The external account ("%s") you just authenticated with is '.
               'not configured to allow account linking on this Phabricator '.
-              'install. An administrator may have recently disabled it.'));
+              'install. An administrator may have recently disabled it.',
+              $provider->getProviderName()));
         }
       }
     }
@@ -90,8 +91,20 @@ final class PhabricatorAuthLoginController
   }
 
   private function processLoginUser(PhabricatorExternalAccount $account) {
-    // TODO: Implement.
-    return new Aphront404Response();
+    $user = id(new PhabricatorUser())->loadOneWhere(
+      'phid = %s',
+      $account->getUserPHID());
+
+    if (!$user) {
+      return $this->renderError(
+        pht(
+          'The external account you just logged in with is not associated '.
+          'with a valid Phabricator user.'));
+    }
+
+    $this->establishWebSession($user);
+
+    return $this->buildLoginValidateResponse($user);
   }
 
   private function processRegisterUser(PhabricatorExternalAccount $account) {

src/applications/auth/controller/PhabricatorAuthStartController.php

@@ -138,20 +138,9 @@ final class PhabricatorAuthStartController
   }
 
   private function renderError($message) {
-    $title = pht('Authentication Failure');
-
-    $view = new AphrontErrorView();
-    $view->setTitle($title);
-    $view->appendChild($message);
-
-    return $this->buildApplicationPage(
-      $view,
-      array(
-        'title' => $title,
-        'device' => true,
-        'dust' => true,
-      ));
+    return $this->renderErrorPage(
+      pht('Authentication Failure'),
+      array($message));
   }
 
-
 }

src/applications/auth/controller/PhabricatorAuthValidateController.php

@@ -0,0 +1,73 @@
+<?php
+
+final class PhabricatorAuthValidateController
+  extends PhabricatorAuthController {
+
+  public function shouldRequireLogin() {
+    return false;
+  }
+
+  public function processRequest() {
+    $request = $this->getRequest();
+    $viewer = $request->getUser();
+
+    $failures = array();
+
+    if (!strlen($request->getStr('phusr'))) {
+      return $this->renderErrors(
+        array(
+          pht(
+            'Login validation is missing expected parameter ("%s").',
+            'phusr')));
+    }
+
+    $expect_phusr = $request->getStr('phusr');
+    $actual_phusr = $request->getCookie('phusr');
+    if ($actual_phusr != $expect_phusr) {
+      if ($actual_phusr) {
+        $failures[] = pht(
+          "Attempted to set '%s' cookie to '%s', but your browser sent back ".
+          "a cookie with the value '%s'. Clear your browser's cookies and ".
+          "try again.",
+          'phusr',
+          $expect_phusr,
+          $actual_phusr);
+      } else {
+        $failures[] = pht(
+          "Attempted to set '%s' cookie to '%s', but your browser did not ".
+          "accept the cookie. Check that cookies are enabled, clear them, ".
+          "and try again.",
+          'phusr',
+          $expect_phusr);
+      }
+    }
+
+    if (!$failures) {
+      if (!$viewer->getPHID()) {
+        $failures[] = pht(
+          "Login cookie was set correctly, but your login session is not ".
+          "valid. Try clearing cookies and logging in again.");
+      }
+    }
+
+    if ($failures) {
+      return $this->renderErrors($failures);
+    }
+
+    $next = $request->getCookie('next_uri');
+    $request->clearCookie('next_uri');
+
+    if (!PhabricatorEnv::isValidLocalWebResource($next)) {
+      $next = '/';
+    }
+
+    return id(new AphrontRedirectResponse())->setURI($next);
+  }
+
+  private function renderErrors(array $messages) {
+    return $this->renderErrorPage(
+      pht('Login Failure'),
+      $messages);
+  }
+
+}