org.owasp.html.Sanitizers Maven / Gradle / Ivy
// Copyright (c) 2011, Mike Samuel
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// Neither the name of the OWASP nor the names of its contributors may
// be used to endorse or promote products derived from this software
// without specific prior written permission.
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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// POSSIBILITY OF SUCH DAMAGE.
package org.owasp.html;
/**
* Pre-packaged HTML sanitizer policies.
*
*
* These policies can be used to sanitize content.
*
*
* Sanitizers.FORMATTING.sanitize({@code "Hello, World!"})
*
* and can be chained
*
* PolicyFactory sanitizer = Sanitizers.FORMATTING.and(Sanitizers.BLOCKS);
* System.out.println(sanitizer.sanitize({@code "Hello, World!"}));
*
*
*
* For more fine-grained control over sanitization, use
* {@link HtmlPolicyBuilder}.
*
*
* @author Mike Samuel
*/
public final class Sanitizers {
/**
* Allows common formatting elements including {@code }, {@code }, etc.
*/
public static final PolicyFactory FORMATTING = new HtmlPolicyBuilder()
.allowCommonInlineFormattingElements().toFactory();
/**
* Allows common block elements including <p>,
* <h1>, etc.
*/
public static final PolicyFactory BLOCKS = new HtmlPolicyBuilder()
.allowCommonBlockElements().toFactory();
/**
* Allows certain safe CSS properties in {@code style="..."} attributes.
*/
public static final PolicyFactory STYLES = new HtmlPolicyBuilder()
.allowStyling().toFactory();
/**
* Allows HTTP, HTTPS, MAILTO, and relative links.
*/
public static final PolicyFactory LINKS = new HtmlPolicyBuilder()
.allowStandardUrlProtocols().allowElements("a")
.allowAttributes("href").onElements("a").requireRelNofollowOnLinks()
.toFactory();
private static final AttributePolicy INTEGER = new AttributePolicy() {
public String apply(
String elementName, String attributeName, String value) {
int n = value.length();
if (n == 0) { return null; }
for (int i = 0; i < n; ++i) {
char ch = value.charAt(i);
if (ch == '.') {
if (i == 0) { return null; }
return value.substring(0, i); // truncate to integer.
} else if (!('0' <= ch && ch <= '9')) {
return null;
}
}
return value;
}
};
/**
* Allows {@code ![]()
} elements from HTTP, HTTPS, and relative sources.
*/
public static final PolicyFactory IMAGES = new HtmlPolicyBuilder()
.allowUrlProtocols("http", "https").allowElements("img")
.allowAttributes("alt", "src").onElements("img")
.allowAttributes("border", "height", "width").matching(INTEGER)
.onElements("img")
.toFactory();
private Sanitizers() {
// Uninstantiable.
}
}