diff --git a/core/lib/Drupal/Core/CoreServiceProvider.php b/core/lib/Drupal/Core/CoreServiceProvider.php
index a6cb957..50a2ff0 100644
--- a/core/lib/Drupal/Core/CoreServiceProvider.php
+++ b/core/lib/Drupal/Core/CoreServiceProvider.php
@@ -108,6 +108,11 @@ public static function registerTwig(ContainerBuilder $container) {
       ->addArgument(DRUPAL_ROOT);
     $container->setAlias('twig.loader', 'twig.loader.filesystem');
 
+    $twig_extension = new Definition('Drupal\Core\Template\TwigExtension');
+    // When in the installer these services are not yet available.
+    if (!drupal_installation_attempted()) {
+      $twig_extension->addMethodCall('setGenerators', array(new Reference('url_generator'), new Reference('link_generator')));
+    }
     $container->register('twig', 'Drupal\Core\Template\TwigEnvironment')
       ->addArgument(new Reference('twig.loader'))
       ->addArgument(array(
@@ -127,7 +132,7 @@ public static function registerTwig(ContainerBuilder $container) {
         'debug' => settings()->get('twig_debug', FALSE),
         'auto_reload' => settings()->get('twig_auto_reload', NULL),
       ))
-      ->addMethodCall('addExtension', array(new Definition('Drupal\Core\Template\TwigExtension')))
+      ->addMethodCall('addExtension', array($twig_extension))
       // @todo Figure out what to do about debugging functions.
       // @see http://drupal.org/node/1804998
       ->addMethodCall('addExtension', array(new Definition('Twig_Extension_Debug')));
diff --git a/core/lib/Drupal/Core/Routing/UrlGenerator.php b/core/lib/Drupal/Core/Routing/UrlGenerator.php
index 53ac95d..eb3d5f7 100644
--- a/core/lib/Drupal/Core/Routing/UrlGenerator.php
+++ b/core/lib/Drupal/Core/Routing/UrlGenerator.php
@@ -197,10 +197,17 @@ public function generateFromRoute($name, $parameters = array(), $options = array
       $scheme = $req;
     }
     $port = '';
-    if ('http' === $scheme && 80 != $this->context->getHttpPort()) {
-      $port = ':' . $this->context->getHttpPort();
-    } elseif ('https' === $scheme && 443 != $this->context->getHttpsPort()) {
-      $port = ':' . $this->context->getHttpsPort();
+    if ('http' === $scheme) {
+      $http_port = $this->context->getHttpPort();
+      if ($http_port && $http_port != 80) {
+        $port = ':' . $http_port;
+      }
+    }
+    elseif ('https' === $scheme) {
+      $https_port = $this->context->getHttpsPort();
+      if ($https_port && $https_port != 443) {
+        $port = ':' . $https_port;
+      }
     }
     return $scheme . '://' . $host . $port . $base_url . $path . $fragment;
   }
diff --git a/core/lib/Drupal/Core/Template/TwigExtension.php b/core/lib/Drupal/Core/Template/TwigExtension.php
index 9cd17b0..b26d169 100644
--- a/core/lib/Drupal/Core/Template/TwigExtension.php
+++ b/core/lib/Drupal/Core/Template/TwigExtension.php
@@ -10,6 +10,8 @@
  */
 
 namespace Drupal\Core\Template;
+use Drupal\Core\Routing\UrlGeneratorInterface;
+use Drupal\Core\Utility\LinkGeneratorInterface;
 
 /**
  * A class for providing Twig extensions (specific Twig_NodeVisitors, filters and functions).
@@ -17,11 +19,41 @@
  * @see \Drupal\Core\CoreServiceProvider
  */
 class TwigExtension extends \Twig_Extension {
+
+  /**
+   * The URL generator.
+   *
+   * @var \Drupal\Core\Routing\UrlGeneratorInterface
+   */
+  protected $urlGenerator;
+
+  /**
+   * The link generator.
+   *
+   * @var \Drupal\Core\Utility\LinkGeneratorInterface
+   */
+  protected $linkGenerator;
+
+  /**
+   * Constructs \Drupal\Core\Template\TwigExtension.
+   *
+   * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
+   *   The URL generator.
+   * @param \Drupal\Core\Utility\LinkGeneratorInterface $link_generator
+   *   The link generator.
+   */
+  public function setGenerators(UrlGeneratorInterface $url_generator, LinkGeneratorInterface $link_generator) {
+    $this->urlGenerator = $url_generator;
+    $this->linkGenerator = $link_generator;
+  }
+
   public function getFunctions() {
     // @todo re-add unset => twig_unset if this is really needed
     return array(
       // @todo Remove URL function once http://drupal.org/node/1778610 is resolved.
-      'url' => new \Twig_Function_Function('url'),
+      'url_from_path' => new \Twig_SimpleFunction('url_from_path', array($this, 'generateFromPath')),
+      'url' => new \Twig_SimpleFunction('url', array($this, 'generateUrl')),
+      'link' => new \Twig_SimpleFunction('link', array($this, 'generateLink'), array('is_safe' => array('html'))),
       // These functions will receive a TwigReference object, if a render array is detected
       'hide' => new TwigReferenceFunction('twig_hide'),
       'render_var' => new TwigReferenceFunction('twig_render_var'),
@@ -63,5 +95,32 @@ public function getName()
   {
     return 'drupal_core';
   }
+
+  /**
+   * Generates a URL using the route generator.
+   *
+   * @see \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute()
+   */
+  public function generateUrl($route_name, $route_parameters = array(), $options = array()) {
+    return $this->urlGenerator->generateFromRoute($route_name, $route_parameters, $options);
+  }
+
+  /**
+   * Generates a URL using the route generator and the method generateFromPath.
+   *
+   * @see \Drupal\Core\Routing\UrlGeneratorInterface::generateFromPath()
+   */
+  public function generateFromPath($path, $options = array()) {
+    return $this->urlGenerator->generateFromPath($path, $options);
+  }
+
+  /**
+   * Generates a link (A tag) using the link generator.
+   *
+   * @see \Drupal\Core\Utility\LinkGeneratorInterface::generate()
+   */
+  public function generateLink($text, $route_name, $route_parameters = array(), $options = array()) {
+    return $this->linkGenerator->generate($text, $route_name, $route_parameters, $options);
+  }
 }
 
diff --git a/core/modules/system/lib/Drupal/system/Tests/Theme/ThemeTestTwig.php b/core/modules/system/lib/Drupal/system/Tests/Theme/ThemeTestTwig.php
index 2dce51f..511c00b 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Theme/ThemeTestTwig.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Theme/ThemeTestTwig.php
@@ -47,4 +47,30 @@ function testTwigVariableDataTypes() {
     }
   }
 
+  /**
+   * Tests the url and url_generate Twig function.
+   */
+  public function testTwigUrlGenerator() {
+    $this->drupalGet('twig-theme-test/url-generator');
+    // Find the absolute URL of the current site.
+    $url_generator = $this->container->get('url_generator');
+    $link_generator = $this->container->get('link_generator');
+    $expected = array(
+      'url_from_path not absolute: ' . $url_generator->generateFromPath('user/register'),
+      'url_from_path absolute: ' . $url_generator->generateFromPath('user/register', array('absolute' => TRUE)),
+      'url not absolute: ' . $url_generator->generateFromRoute('user.register'),
+      'url absolute: ' . $url_generator->generateFromRoute('user.register', array(), array('absolute' => TRUE)),
+      'url absolute with fragment: ' . $url_generator->generateFromRoute('user.register', array(), array('absolute' => TRUE, 'fragment' => 'bottom')),
+      'link not absolute: ' . $link_generator->generate('Register', 'user.register'),
+      'link absolute: ' . $link_generator->generate('Register', 'user.register', array(), array('absolute' => TRUE)),
+      'link absolute with fragment: ' . $link_generator->generate('Register', 'user.register', array(), array('absolute' => TRUE, 'fragment' => 'bottom')),
+    );
+    // Make sure we got something.
+    $content = $this->drupalGetContent();
+    $this->assertFalse(empty($content), 'Page content is not empty');
+    foreach ($expected as $string) {
+      $this->assertRaw('<div>' . $string . '</div>');
+    }
+  }
+
 }
diff --git a/core/modules/system/tests/modules/twig_theme_test/lib/Drupal/twig_theme_test/TwigThemeTestController.php b/core/modules/system/tests/modules/twig_theme_test/lib/Drupal/twig_theme_test/TwigThemeTestController.php
index 9179de9..ced7226 100644
--- a/core/modules/system/tests/modules/twig_theme_test/lib/Drupal/twig_theme_test/TwigThemeTestController.php
+++ b/core/modules/system/tests/modules/twig_theme_test/lib/Drupal/twig_theme_test/TwigThemeTestController.php
@@ -38,4 +38,13 @@ public function transBlockRender() {
     );
   }
 
+  /**
+   * Renders for testing url_generator functions in a Twig template.
+   */
+  public function urlGeneratorRender() {
+    return array(
+      '#theme' => 'twig_theme_test_url_generator',
+    );
+  }
+
 }
diff --git a/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.url_generator.html.twig b/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.url_generator.html.twig
new file mode 100644
index 0000000..70c2179
--- /dev/null
+++ b/core/modules/system/tests/modules/twig_theme_test/templates/twig_theme_test.url_generator.html.twig
@@ -0,0 +1,20 @@
+{# Test the url_from_path twig function #}
+<div>url_from_path not absolute: {{ url_from_path('user/register') }}</div>
+
+<div>url_from_path absolute: {{ url_from_path('user/register', {'absolute': 1 }) }}</div>
+
+{# Test the url twig function #}
+
+<div>url not absolute: {{ url('user.register') }}</div>
+
+<div>url absolute: {{ url('user.register', {}, {'absolute': '1' }) }}</div>
+
+<div>url absolute with fragment: {{ url('user.register', {}, {'absolute': '1', 'fragment': 'bottom' }) }}</div>
+
+{# Test the link twig function #}
+
+<div>link not absolute: {{ link('Register', 'user.register') }}</div>
+
+<div>link absolute: {{ link('Register', 'user.register', {}, {'absolute': '1' }) }}</div>
+
+<div>link absolute with fragment: {{ link('Register', 'user.register', {}, {'absolute': '1', 'fragment': 'bottom' }) }}</div>
diff --git a/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.module b/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.module
index 934d1b0..fc51628 100644
--- a/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.module
+++ b/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.module
@@ -11,6 +11,10 @@ function twig_theme_test_theme($existing, $type, $theme, $path) {
     'variables' => array(),
     'template' => 'twig_theme_test.trans',
   );
+  $items['twig_theme_test_url_generator'] = array(
+    'variables' => array(),
+    'template' => 'twig_theme_test.url_generator',
+  );
   return $items;
 }
 
diff --git a/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.routing.yml b/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.routing.yml
index 07880fb..904e0ea 100644
--- a/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.routing.yml
+++ b/core/modules/system/tests/modules/twig_theme_test/twig_theme_test.routing.yml
@@ -11,3 +11,9 @@ twig_theme_test.trans:
     _content: '\Drupal\twig_theme_test\TwigThemeTestController::transBlockRender'
   requirements:
     _permission: 'access content'
+twig_theme_test_url_generator:
+  path: '/twig-theme-test/url-generator'
+  defaults:
+    _content: '\Drupal\twig_theme_test\TwigThemeTestController::urlGeneratorRender'
+  requirements:
+    _permission: 'access content'
diff --git a/core/scripts/run-tests.sh b/core/scripts/run-tests.sh
index 31ea371..e728abe 100755
--- a/core/scripts/run-tests.sh
+++ b/core/scripts/run-tests.sh
@@ -301,6 +301,7 @@ function simpletest_script_init($server_software) {
   }
 
   $_SERVER['HTTP_HOST'] = $host;
+  $_SERVER['SERVER_PORT'] =  isset($parsed_url['port']) ? $parsed_url['port'] : 80;
   $_SERVER['REMOTE_ADDR'] = '127.0.0.1';
   $_SERVER['SERVER_ADDR'] = '127.0.0.1';
   $_SERVER['SERVER_SOFTWARE'] = $server_software;