From 30d67a65466976c90e94c571834d041cc4d8fb5e Mon Sep 17 00:00:00 2001
From: Greg Bowler <greg.bowler@g105b.com>
Date: Fri, 23 Sep 2022 13:03:51 +0100
Subject: [PATCH] feature: multiple tokens exposed with comma separated meta
 content (#174)

closes #44
---
 src/HTMLDocumentProtector.php              | 25 ++++++++++++----------
 test/phpunit/HTMLDocumentProtectorTest.php | 13 +++++++++++
 2 files changed, 27 insertions(+), 11 deletions(-)

diff --git a/src/HTMLDocumentProtector.php b/src/HTMLDocumentProtector.php
index 4e8ca9d..6c2b7d5 100644
--- a/src/HTMLDocumentProtector.php
+++ b/src/HTMLDocumentProtector.php
@@ -52,17 +52,24 @@ public function protect(
 		string $tokenSharing = self::ONE_TOKEN_PER_PAGE
 	):string {
 		$forms = $this->document->forms;
+		$tokenArray = [];
 
-		if($forms->length > 0) {
-			$token = $this->tokenStore->generateNewToken();
-			$this->tokenStore->saveToken($token);
+		$token = null;
 
+		if($forms->length > 0) {
 			foreach($forms as $form) {
 				$formMethod = $form->getAttribute("method");
 				if(strtolower($formMethod) !== "post") {
 					continue;
 				}
 
+				if($tokenSharing === self::ONE_TOKEN_PER_FORM
+				|| is_null($token)) {
+					$token = $this->tokenStore->generateNewToken();
+					$this->tokenStore->saveToken($token);
+					array_push($tokenArray, $token);
+				}
+
 				$csrfElement = $this->document->createElement(
 					"input"
 				);
@@ -82,16 +89,13 @@ public function protect(
 					$csrfElement,
 					$form->firstChild
 				);
-
-				if($tokenSharing === self::ONE_TOKEN_PER_FORM) {
-					$token = $this->tokenStore->generateNewToken();
-					$this->tokenStore->saveToken($token);
-				}
 			}
 		}
-		else {
+
+		if(is_null($token)) {
 			$token = $this->tokenStore->generateNewToken();
 			$this->tokenStore->saveToken($token);
+			array_push($tokenArray, $token);
 		}
 
 		$meta = $this->document->querySelector(
@@ -123,8 +127,7 @@ public function protect(
 			$head->appendChild($meta);
 		}
 
-		$meta->setAttribute("content", $token);
-
+		$meta->setAttribute("content", implode(",", $tokenArray));
 		return $token;
 	}
 
diff --git a/test/phpunit/HTMLDocumentProtectorTest.php b/test/phpunit/HTMLDocumentProtectorTest.php
index 22c51f3..a8bc9d6 100644
--- a/test/phpunit/HTMLDocumentProtectorTest.php
+++ b/test/phpunit/HTMLDocumentProtectorTest.php
@@ -253,6 +253,19 @@ public function testProtect_metaTagAlreadyExists():void {
 		self::assertNotEquals($originalValue, $metaTag->content);
 	}
 
+	public function testProtect_metaTagMultipleForms():void {
+		$document = new HTMLDocument(self::THREE_FORMS);
+		$sut = new HTMLDocumentProtector($document, new ArrayTokenStore());
+		$sut->protect(HTMLDocumentProtector::ONE_TOKEN_PER_FORM);
+
+		$nodeList = $document->querySelectorAll("head meta[name='" . HTMLDocumentProtector::TOKEN_NAME . "']");
+// There should still only be 1 meta tag...
+		self::assertCount(1, $nodeList);
+// ... but the tag's content should have two values (one per POST form).
+		$tokenArray = explode(",", $nodeList[0]->content);
+		self::assertCount(2, $tokenArray);
+	}
+
 	public function testProtect_differentTokenName() {
 		$sut = new HTMLDocumentProtector(new HTMLDocument(self::HAS_META_ALREADY), new ArrayTokenStore());
 		$tokenName = HTMLDocumentProtector::TOKEN_NAME;