Adds support for "SameSite" cookie property

app/code/core/Mage/Adminhtml/Model/System/Config/Source/Cookie/SameSite.php

@@ -0,0 +1,16 @@
+<?php
+
+class Mage_Adminhtml_Model_System_Config_Source_Cookie_SameSite
+{
+    /**
+     * @return array[]
+     */
+    public function toOptionArray(): array
+    {
+        return [
+            ['value' => 'None', 'label' => Mage::helper('adminhtml')->__('None')],
+            ['value' => 'Strict', 'label' => Mage::helper('adminhtml')->__('Strict')],
+            ['value' => 'Lax', 'label' => Mage::helper('adminhtml')->__('Lax')]
+        ];
+    }
+}

app/code/core/Mage/Core/Model/Cookie.php

@@ -37,6 +37,7 @@ class Mage_Core_Model_Cookie
     const XML_PATH_COOKIE_PATH      = 'web/cookie/cookie_path';
     const XML_PATH_COOKIE_LIFETIME  = 'web/cookie/cookie_lifetime';
     const XML_PATH_COOKIE_HTTPONLY  = 'web/cookie/cookie_httponly';
+    const XML_PATH_COOKIE_SAMESITE  = 'web/cookie/cookie_samesite';
 
     protected $_lifetime;
 
@@ -174,6 +175,20 @@ public function getHttponly()
         return (bool)$httponly;
     }
 
+    /**
+     * Retrieve use SameSite
+     *
+     * @return string
+     */
+    public function getSameSite(): string
+    {
+        $sameSite = Mage::getStoreConfig(self::XML_PATH_COOKIE_SAMESITE, $this->getStore());
+        if (is_null($sameSite)) {
+            return 'None';
+        }
+        return (string)$sameSite;
+    }
+
     /**
      * Is https secure request
      * Use secure on adminhtml only
@@ -202,9 +217,10 @@ public function isSecure()
      * @param string $domain
      * @param int|bool $secure
      * @param bool $httponly
+     * @param string $sameSite
      * @return $this
      */
-    public function set($name, $value, $period = null, $path = null, $domain = null, $secure = null, $httponly = null)
+    public function set($name, $value, $period = null, $path = null, $domain = null, $secure = null, $httponly = null, $sameSite = null)
     {
         /**
          * Check headers sent
@@ -236,8 +252,34 @@ public function set($name, $value, $period = null, $path = null, $domain = null,
         if (is_null($httponly)) {
             $httponly = $this->getHttponly();
         }
+        if (is_null($sameSite)) {
+            $sameSite = $this->getSameSite();
+        }
 
-        setcookie($name, $value, $expire, $path, $domain, $secure, $httponly);
+        if ($sameSite === 'None') {
+            // Enforce specification SameSite None requires secure
+            $secure = true;
+        }
+
+        if (PHP_VERSION_ID >= 70300) {
+            setcookie(
+                $name,
+                $value,
+                [
+                    'expires'  => $expire,
+                    'path'     => $path,
+                    'domain'   => $domain,
+                    'secure'   => $secure,
+                    'httponly' => $httponly,
+                    'samesite' => $sameSite
+                ]
+            );
+        } else {
+            if (!empty($sameSite)) {
+                $path.= "; samesite=${sameSite}";
+            }
+            setcookie($name, $value, $expire, $path, $domain, $secure, $httponly);
+        }
 
         return $this;
     }
@@ -251,16 +293,17 @@ public function set($name, $value, $period = null, $path = null, $domain = null,
      * @param string $domain
      * @param int|bool $secure
      * @param bool $httponly
+     * @param string $sameSite
      * @return $this
      */
-    public function renew($name, $period = null, $path = null, $domain = null, $secure = null, $httponly = null)
+    public function renew($name, $period = null, $path = null, $domain = null, $secure = null, $httponly = null, $sameSite = null)
     {
         if (($period === null) && !$this->getLifetime()) {
             return $this;
         }
         $value = $this->_getRequest()->getCookie($name, false);
         if ($value !== false) {
-            $this->set($name, $value, $period, $path, $domain, $secure, $httponly);
+            $this->set($name, $value, $period, $path, $domain, $secure, $httponly, $sameSite);
         }
         return $this;
     }
@@ -284,9 +327,10 @@ public function get($name = null)
      * @param string $domain
      * @param int|bool $secure
      * @param int|bool $httponly
+     * @param string $sameSite
      * @return $this
      */
-    public function delete($name, $path = null, $domain = null, $secure = null, $httponly = null)
+    public function delete($name, $path = null, $domain = null, $secure = null, $httponly = null, $sameSite = null)
     {
         /**
          * Check headers sent
@@ -295,20 +339,6 @@ public function delete($name, $path = null, $domain = null, $secure = null, $htt
             return $this;
         }
 
-        if (is_null($path)) {
-            $path = $this->getPath();
-        }
-        if (is_null($domain)) {
-            $domain = $this->getDomain();
-        }
-        if (is_null($secure)) {
-            $secure = $this->isSecure();
-        }
-        if (is_null($httponly)) {
-            $httponly = $this->getHttponly();
-        }
-
-        setcookie($name, null, null, $path, $domain, $secure, $httponly);
-        return $this;
+        return $this->set($name, null, null, $path, $domain, $secure, $httponly, $sameSite);
     }
 }

app/code/core/Mage/Core/etc/config.xml

@@ -407,6 +407,7 @@
             <cookie>
                 <cookie_lifetime>3600</cookie_lifetime>
                 <cookie_httponly>1</cookie_httponly>
+                <cookie_samesite>None</cookie_samesite>
                 <cookie_restriction>0</cookie_restriction>
                 <cookie_restriction_lifetime>31536000</cookie_restriction_lifetime>
             </cookie>

app/code/core/Mage/Core/etc/system.xml

@@ -1574,6 +1574,16 @@
                             <show_in_website>1</show_in_website>
                             <show_in_store>1</show_in_store>
                         </cookie_httponly>
+                        <cookie_samesite translate="label">
+                            <label>Same-Site</label>
+                            <frontend_type>select</frontend_type>
+                            <source_model>adminhtml/system_config_source_cookie_samesite</source_model>
+                            <comment><![CDATA[<a target="_blank" href="https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00"/>https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00</a>]]></comment>
+                            <sort_order>45</sort_order>
+                            <show_in_default>1</show_in_default>
+                            <show_in_website>1</show_in_website>
+                            <show_in_store>1</show_in_store>
+                        </cookie_samesite>
                         <cookie_restriction translate="label">
                             <label>Cookie Restriction Mode</label>
                             <frontend_type>select</frontend_type>

app/locale/en_US/Mage_Core.csv

@@ -397,6 +397,10 @@
 "Use Custom Admin Path","Use Custom Admin Path"
 "Use Custom Admin URL","Use Custom Admin URL"
 "Use HTTP Only","Use HTTP Only"
+"Same-Site","Same-Site"
+"None","None"
+"Strict","Strict"
+"Lax","Lax"
 "Use SID on Frontend","Use SID on Frontend"
 "Use Secure URLs in Admin","Use Secure URLs in Admin"
 "Use Secure URLs in Frontend","Use Secure URLs in Frontend"