| package org.apache.archiva.redback.rest.services.interceptors; |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 |
| * |
| * http://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. |
| */ |
| |
| |
| import org.apache.archiva.redback.configuration.UserConfiguration; |
| import org.apache.cxf.jaxrs.utils.JAXRSUtils; |
| import org.apache.cxf.message.Message; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| import org.springframework.stereotype.Service; |
| |
| import javax.annotation.PostConstruct; |
| import javax.inject.Inject; |
| import javax.inject.Named; |
| import javax.servlet.http.HttpServletRequest; |
| import javax.ws.rs.container.ContainerRequestContext; |
| import javax.ws.rs.container.ContainerRequestFilter; |
| import javax.ws.rs.core.Response; |
| import javax.ws.rs.ext.Provider; |
| import java.io.IOException; |
| import java.net.MalformedURLException; |
| import java.net.URL; |
| |
| /** |
| * Created by Martin Stockhammer on 19.01.17. |
| * |
| * This interceptor tries to check if requests come from a valid origin and |
| * are not generated by another site on behalf of the real client. |
| * |
| * We are using some of the techniques mentioned in |
| * https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF)_Prevention_Cheat_Sheet |
| * |
| * Try to find Origin and Referer of the request. |
| * Match them to the target address, that may be either statically configured or is determined |
| * by the Host/X-Forwarded-For Header. |
| * |
| * |
| */ |
| @Provider |
| @Service( "requestValidationInterceptor#rest" ) |
| public class RequestValidationInterceptor extends AbstractInterceptor implements ContainerRequestFilter { |
| |
| |
| private static final String X_FORWARDED_PROTO = "X-Forwarded-Proto"; |
| private static final String X_FORWARDED_HOST = "X-Forwarded-Host"; |
| private static final String ORIGIN = "Origin"; |
| private static final String REFERER = "Referer"; |
| private static final String CFG_REST_BASE_URL = "rest.baseUrl"; |
| private static final String CFG_REST_CSRF_ABSENTORIGIN_DENY = "rest.csrffilter.absentorigin.deny"; |
| private static final String CFG_REST_CSRF_ENABLED = "rest.csrffilter.enabled"; |
| |
| private final Logger log = LoggerFactory.getLogger( getClass() ); |
| |
| private boolean enabled = true; |
| private boolean useStaticUrl = false; |
| private boolean denyAbsentHeaders = true; |
| private URL baseUrl; |
| private HttpServletRequest httpRequest = null; |
| |
| private UserConfiguration config; |
| |
| @Inject |
| public RequestValidationInterceptor(@Named( value = "userConfiguration#default" ) |
| UserConfiguration config) { |
| this.config = config; |
| } |
| |
| @PostConstruct |
| public void init() { |
| String baseUrlStr = config.getString(CFG_REST_BASE_URL, ""); |
| if (!"".equals(baseUrlStr.trim())) { |
| try { |
| baseUrl = new URL(baseUrlStr); |
| useStaticUrl = true; |
| } catch (MalformedURLException ex) { |
| log.error("Configured baseUrl (rest.baseUrl={}) is invalid. Message: {}", baseUrlStr, ex.getMessage()); |
| } |
| } else { |
| useStaticUrl = false; |
| } |
| denyAbsentHeaders = config.getBoolean(CFG_REST_CSRF_ABSENTORIGIN_DENY,true); |
| enabled = config.getBoolean(CFG_REST_CSRF_ENABLED,true); |
| if (!enabled) { |
| log.info("CSRF Filter is disabled by configuration"); |
| } |
| } |
| |
| @Override |
| public void filter(ContainerRequestContext containerRequestContext) throws IOException { |
| if (enabled) { |
| HttpServletRequest request = getRequest(); |
| URL targetUrl = getTargetUrl(request); |
| if (targetUrl == null) { |
| log.error("Could not verify target URL."); |
| containerRequestContext.abortWith(Response.status(Response.Status.FORBIDDEN).build()); |
| } |
| if (!checkSourceRequestHeader(targetUrl, request)) { |
| log.warn("HTTP Header check failed. Assuming CSRF attack."); |
| containerRequestContext.abortWith(Response.status(Response.Status.FORBIDDEN).build()); |
| } |
| } |
| } |
| |
| private HttpServletRequest getRequest() { |
| if (httpRequest!=null) { |
| return httpRequest; |
| } else { |
| Message message = JAXRSUtils.getCurrentMessage(); |
| return getHttpServletRequest(message); |
| } |
| } |
| |
| private URL getTargetUrl(HttpServletRequest request) { |
| if (useStaticUrl) { |
| return baseUrl; |
| } else { |
| URL requestUrl; |
| try { |
| requestUrl = new URL(request.getRequestURL().toString()); |
| } catch (MalformedURLException ex) { |
| log.error("Bad Request URL {}, Message: {}", request.getRequestURL(), ex.getMessage()); |
| return null; |
| } |
| String xforwarded = request.getHeader(X_FORWARDED_HOST); |
| String xforwardedProto = request.getHeader(X_FORWARDED_PROTO); |
| if (xforwardedProto==null) { |
| xforwardedProto=requestUrl.getProtocol(); |
| } |
| if (xforwarded!=null) { |
| try { |
| return new URL(xforwardedProto+"://"+xforwarded); |
| } catch (MalformedURLException ex) { |
| log.warn("X-Forwarded-Host Header is malformed: {}", ex.getMessage()); |
| } |
| } |
| return requestUrl; |
| } |
| } |
| |
| private int getPort(final URL url) { |
| return url.getPort() > 0 ? url.getPort() : url.getDefaultPort(); |
| } |
| |
| private boolean checkSourceRequestHeader(final URL targetUrl, final HttpServletRequest request) { |
| boolean headerFound=false; |
| String origin = request.getHeader(ORIGIN); |
| int targetPort = getPort(targetUrl); |
| if (origin!=null) { |
| try { |
| URL originUrl = new URL(origin); |
| headerFound=true; |
| log.debug("Origin Header URL found: {}", originUrl); |
| if (!targetUrl.getProtocol().equals(originUrl.getProtocol())) { |
| log.warn("Origin Header Protocol does not match originUrl={}, targetUrl={}", originUrl, targetUrl); |
| return false; |
| } |
| if (!targetUrl.getHost().equals(originUrl.getHost())) { |
| log.warn("Origin Header Host does not match originUrl={}, targetUrl={}",originUrl,targetUrl); |
| return false; |
| } |
| int originPort = getPort(originUrl); |
| if (targetPort != originPort) { |
| log.warn("Origin Header Port does not match originUrl={}, targetUrl={}",originUrl,targetUrl); |
| return false; |
| } |
| } catch (MalformedURLException ex) { |
| log.warn("Bad URL in Origin HTTP-Header: {}. Message: {}",origin, ex.getMessage()); |
| return false; |
| } |
| } |
| String referer = request.getHeader(REFERER); |
| if (referer!=null) { |
| try { |
| URL refererUrl = new URL(referer); |
| headerFound=true; |
| log.debug("Referer Header URL found: {}",refererUrl); |
| if (!targetUrl.getHost().equals(refererUrl.getHost())) { |
| log.warn("Referer Header Host does not match refererUrl={}, targetUrl={}",refererUrl,targetUrl); |
| return false; |
| } |
| int refererPort = getPort(refererUrl); |
| if (targetPort != refererPort) { |
| log.warn("Referer Header Port does not match refererUrl={}, targetUrl={}",refererUrl,targetUrl); |
| return false; |
| } |
| } catch (MalformedURLException ex) { |
| log.warn("Bad URL in Referer HTTP-Header: {}, Message: {}", referer, ex.getMessage()); |
| return false; |
| } |
| } |
| if (!headerFound && denyAbsentHeaders) { |
| log.warn("Neither Origin nor Referer header found. Request is denied."); |
| return false; |
| } |
| return true; |
| } |
| |
| public void setHttpRequest(HttpServletRequest request) { |
| this.httpRequest = request; |
| } |
| } |