org.springframework.security.web.header.writers.ClearSiteDataHeaderWriter Maven / Gradle / Ivy
/*
* Copyright 2002-2019 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.security.web.header.writers;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.security.web.header.HeaderWriter;
import org.springframework.security.web.util.matcher.RequestMatcher;
import org.springframework.util.Assert;
/**
* Provides support for Clear
* Site Data.
*
*
* Developers may instruct a user agent to clear various types of relevant data by delivering
* a Clear-Site-Data HTTP response header in response to a request.
*
*
*
* Due to Incomplete Clearing
* section the header is only applied if the request is secure.
*
*
* @author Rafiullah Hamedy
* @since 5.2
*/
public final class ClearSiteDataHeaderWriter implements HeaderWriter {
private static final String CLEAR_SITE_DATA_HEADER = "Clear-Site-Data";
private final Log logger = LogFactory.getLog(getClass());
private final RequestMatcher requestMatcher;
private String headerValue;
/**
*
* Creates a new instance of {@link ClearSiteDataHeaderWriter} with given sources.
* The constructor also initializes requestMatcher with a new instance of
* SecureRequestMatcher to ensure that header is only applied if and when
* the request is secure as per the Incomplete Clearing section.
*
*
* @param directives (i.e. "cache", "cookies", "storage", "executionContexts" or "*")
* @throws {@link IllegalArgumentException} if sources is null or empty.
*/
public ClearSiteDataHeaderWriter(Directive... directives) {
Assert.notEmpty(directives, "directives cannot be empty or null");
this.requestMatcher = new SecureRequestMatcher();
this.headerValue = transformToHeaderValue(directives);
}
@Override
public void writeHeaders(HttpServletRequest request, HttpServletResponse response) {
if (this.requestMatcher.matches(request)) {
if (!response.containsHeader(CLEAR_SITE_DATA_HEADER)) {
response.setHeader(CLEAR_SITE_DATA_HEADER, this.headerValue);
}
} else if (logger.isDebugEnabled()) {
logger.debug("Not injecting Clear-Site-Data header since it did not match the "
+ "requestMatcher " + this.requestMatcher);
}
}
/**
* Represents the directive values expected by the {@link ClearSiteDataHeaderWriter}
.
*/
public enum Directive {
CACHE("cache"),
COOKIES("cookies"),
STORAGE("storage"),
EXECUTION_CONTEXTS("executionContexts"),
ALL("*");
private final String headerValue;
Directive(String headerValue) {
this.headerValue = "\"" + headerValue + "\"";
}
public String getHeaderValue() {
return this.headerValue;
}
}
private String transformToHeaderValue(Directive... directives) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < directives.length - 1; i++) {
sb.append(directives[i].headerValue).append(", ");
}
sb.append(directives[directives.length - 1].headerValue);
return sb.toString();
}
private static final class SecureRequestMatcher implements RequestMatcher {
public boolean matches(HttpServletRequest request) {
return request.isSecure();
}
}
@Override
public String toString() {
return getClass().getName() + " [headerValue=" + this.headerValue + "]";
}
}