From a011650a5f0c0414a5a845203b4b2e61f20ea34f Mon Sep 17 00:00:00 2001
From: Ayesh Karunaratne <ayesh@ayesh.me>
Date: Wed, 23 Dec 2020 17:10:56 +0700
Subject: [PATCH 1/2] IMAP: Disallow direct `new IMAPConnection()` construct

Disallows constructing an `IMAPConnection` class directly with `new IMAPConnection` construct, by throwing an `Error` exception if attempted.
`imap_open` is still the only way to create `IMAPConnection` objects.
---
 ext/imap/php_imap.c                  |  6 ++++++
 ext/imap/tests/imap_constructor.phpt | 15 +++++++++++++++
 2 files changed, 21 insertions(+)
 create mode 100644 ext/imap/tests/imap_constructor.phpt

diff --git a/ext/imap/php_imap.c b/ext/imap/php_imap.c
index 1d909d60654a7..399b7a516576b 100644
--- a/ext/imap/php_imap.c
+++ b/ext/imap/php_imap.c
@@ -170,6 +170,11 @@ static zend_object* imap_object_create(zend_class_entry* ce) {
 	return zobj;
 }
 
+static zend_function *imap_object_get_constructor(zend_object *zobj) {
+	zend_throw_error(NULL, "Cannot directly construct IMAPConnection, use imap_open() instead");
+	return NULL;
+}
+
 static void imap_object_destroy(zend_object *zobj) {
 	php_imap_object *obj = imap_object_from_zend_object(zobj);
 
@@ -483,6 +488,7 @@ PHP_MINIT_FUNCTION(imap)
 
 	memcpy(&imap_object_handlers, &std_object_handlers, sizeof(zend_object_handlers));
 	imap_object_handlers.offset = XtOffsetOf(php_imap_object, std);
+	imap_object_handlers.get_constructor = imap_object_get_constructor;
 	imap_object_handlers.dtor_obj = imap_object_destroy;
 	imap_object_handlers.clone_obj = NULL;
 
diff --git a/ext/imap/tests/imap_constructor.phpt b/ext/imap/tests/imap_constructor.phpt
new file mode 100644
index 0000000000000..bc5da991d18d5
--- /dev/null
+++ b/ext/imap/tests/imap_constructor.phpt
@@ -0,0 +1,15 @@
+--TEST--
+Attempt to instantiate an IMAPConnection directly
+--SKIPIF--
+<?php
+extension_loaded('imap') or die('skip imap extension not available in this build');
+--FILE--
+<?php
+
+try {
+    new IMAPConnection();
+} catch (Error $ex) {
+    echo "Exception: ", $ex->getMessage(), "\n";
+}
+--EXPECT--
+Exception: Cannot directly construct IMAPConnection, use imap_open() instead

From adb338ef3b9a5c8180554e942862fc96f9e85ec0 Mon Sep 17 00:00:00 2001
From: Ayesh Karunaratne <ayesh@ayesh.me>
Date: Wed, 23 Dec 2020 17:12:34 +0700
Subject: [PATCH 2/2] IMAP: Declare `IMAPConnection` class as `final`
 (stub+test)

Updates the `IMAPConnection` class stub to make sure it has the `final` flag, and adds a test to verify it.
---
 ext/imap/php_imap.stub.php     |  2 +-
 ext/imap/tests/imap_final.phpt | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)
 create mode 100644 ext/imap/tests/imap_final.phpt

diff --git a/ext/imap/php_imap.stub.php b/ext/imap/php_imap.stub.php
index 0c597badecf98..580c79cc9bc1e 100644
--- a/ext/imap/php_imap.stub.php
+++ b/ext/imap/php_imap.stub.php
@@ -1,7 +1,7 @@
 <?php
 
 /** @generate-function-entries */
-class IMAPConnection {
+final class IMAPConnection {
 
 }
 
diff --git a/ext/imap/tests/imap_final.phpt b/ext/imap/tests/imap_final.phpt
new file mode 100644
index 0000000000000..a896b4e6c4e8f
--- /dev/null
+++ b/ext/imap/tests/imap_final.phpt
@@ -0,0 +1,11 @@
+--TEST--
+Check that IMAPConnection is declared final
+--SKIPIF--
+<?php
+extension_loaded('imap') or die('skip imap extension not available in this build');
+--FILE--
+<?php
+
+class T extends IMAPConnection {}
+--EXPECTF--
+Fatal error: Class T may not inherit from final class (IMAPConnection) in %s on line %d