Merge pull request #329 from AnzhiZhang/main

Add data to DefaultUrlSanitizer protocols

Author: robinst

commonmark/src/main/java/org/commonmark/renderer/html/DefaultUrlSanitizer.java

@@ -4,15 +4,15 @@
 
 /**
  *
- * Allows http, https and mailto protocols for url.
+ * Allows http, https, mailto, and data protocols for url.
  * Also allows protocol relative urls, and relative urls.
  * Implementation based on https://github.com/OWASP/java-html-sanitizer/blob/f07e44b034a45d94d6fd010279073c38b6933072/src/main/java/org/owasp/html/FilterUrlByProtocolAttributePolicy.java
  */
 public class DefaultUrlSanitizer implements UrlSanitizer {
     private Set<String> protocols;
 
     public DefaultUrlSanitizer() {
-        this(List.of("http", "https", "mailto"));
+        this(List.of("http", "https", "mailto", "data"));
     }
 
     public DefaultUrlSanitizer(Collection<String> protocols) {

commonmark/src/test/java/org/commonmark/test/HtmlRendererTest.java

@@ -93,13 +93,47 @@ public void sanitizedUrlsShouldSetRelNoFollow() {
         assertEquals("<p><a rel=\"nofollow\" href=\"https://google.com\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
     }
 
+    @Test
+    public void sanitizedUrlsShouldAllowSafeProtocols() {
+        Paragraph paragraph = new Paragraph();
+        Link link = new Link();
+        link.setDestination("http://google.com");
+        paragraph.appendChild(link);
+        assertEquals("<p><a rel=\"nofollow\" href=\"http://google.com\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
+
+        paragraph = new Paragraph();
+        link = new Link();
+        link.setDestination("https://google.com");
+        paragraph.appendChild(link);
+        assertEquals("<p><a rel=\"nofollow\" href=\"https://google.com\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
+
+        paragraph = new Paragraph();
+        link = new Link();
+        link.setDestination("mailto:foo@bar.example.com");
+        paragraph.appendChild(link);
+        assertEquals("<p><a rel=\"nofollow\" href=\"mailto:foo@bar.example.com\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
+
+        String image = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAAFiUAABYlAUlSJPAAAAAQSURBVBhXY/iPBVBf8P9/AG8TY51nJdgkAAAAAElFTkSuQmCC";
+        paragraph = new Paragraph();
+        link = new Link();
+        link.setDestination(image);
+        paragraph.appendChild(link);
+        assertEquals("<p><a rel=\"nofollow\" href=\"" + image + "\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
+    }
+
     @Test
     public void sanitizedUrlsShouldFilterDangerousProtocols() {
         Paragraph paragraph = new Paragraph();
         Link link = new Link();
         link.setDestination("javascript:alert(5);");
         paragraph.appendChild(link);
         assertEquals("<p><a rel=\"nofollow\" href=\"\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
+
+        paragraph = new Paragraph();
+        link = new Link();
+        link.setDestination("ftp://google.com");
+        paragraph.appendChild(link);
+        assertEquals("<p><a rel=\"nofollow\" href=\"\"></a></p>\n", sanitizeUrlsRenderer().render(paragraph));
     }
 
     @Test