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/** * 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. */ package org.apache.xml.security.utils.resolver.implementations; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URISyntaxException; import java.net.URI; import java.net.URL; import java.net.URLConnection; import org.apache.xml.security.signature.XMLSignatureInput; import org.apache.xml.security.utils.Base64; import org.apache.xml.security.utils.resolver.ResourceResolverException; import org.apache.xml.security.utils.resolver.ResourceResolverSpi; import org.w3c.dom.Attr; /** * A simple ResourceResolver for HTTP requests. This class handles only 'pure' * HTTP URIs which means without a fragment. The Fragment handling is done by the * {@link ResolverFragment} class. * <BR> * If the user has a corporate HTTP proxy which is to be used, the usage can be * switched on by setting properties for the resolver: * <PRE> * resourceResolver.setProperty("http.proxy.host", "proxy.company.com"); * resourceResolver.setProperty("http.proxy.port", "8080"); * * // if we need a password for the proxy * resourceResolver.setProperty("http.proxy.username", "proxyuser3"); * resourceResolver.setProperty("http.proxy.password", "secretca"); * </PRE> * * @author $Author: coheigea $ * @see <A HREF="http://www.javaworld.com/javaworld/javatips/jw-javatip42_p.html">Java Tip 42: Write Java apps that work with proxy-based firewalls</A> * @see <A HREF="http://java.sun.com/j2se/1.4/docs/guide/net/properties.html">SUN J2SE docs for network properties</A> * @see <A HREF="http://metalab.unc.edu/javafaq/javafaq.html#proxy">The JAVA FAQ Question 9.5: How do I make Java work with a proxy server?</A> */ public class ResolverDirectHTTP extends ResourceResolverSpi { /** {@link org.apache.commons.logging} logging facility */ private static org.apache.commons.logging.Log log = org.apache.commons.logging.LogFactory .getLog(ResolverDirectHTTP.class); /** Field properties[] */ private static final String properties[] = { "http.proxy.host", "http.proxy.port", "http.proxy.username", "http.proxy.password", "http.basic.username", "http.basic.password" }; /** Field HttpProxyHost */ private static final int HttpProxyHost = 0; /** Field HttpProxyPort */ private static final int HttpProxyPort = 1; /** Field HttpProxyUser */ private static final int HttpProxyUser = 2; /** Field HttpProxyPass */ private static final int HttpProxyPass = 3; /** Field HttpProxyUser */ private static final int HttpBasicUser = 4; /** Field HttpProxyPass */ private static final int HttpBasicPass = 5; @Override public boolean engineIsThreadSafe() { return true; } /** * Method resolve * * @param uri * @param baseURI * * @throws ResourceResolverException * @return * $todo$ calculate the correct URI from the attribute and the baseURI */ public XMLSignatureInput engineResolve(Attr uri, String baseURI) throws ResourceResolverException { try { boolean useProxy = false; String proxyHost = engineGetProperty(ResolverDirectHTTP.properties[ResolverDirectHTTP.HttpProxyHost]); String proxyPort = engineGetProperty(ResolverDirectHTTP.properties[ResolverDirectHTTP.HttpProxyPort]); if ((proxyHost != null) && (proxyPort != null)) { useProxy = true; } String oldProxySet = null; String oldProxyHost = null; String oldProxyPort = null; // switch on proxy usage if (useProxy) { if (log.isDebugEnabled()) { log.debug("Use of HTTP proxy enabled: " + proxyHost + ":" + proxyPort); } oldProxySet = System.getProperty("http.proxySet"); oldProxyHost = System.getProperty("http.proxyHost"); oldProxyPort = System.getProperty("http.proxyPort"); System.setProperty("http.proxySet", "true"); System.setProperty("http.proxyHost", proxyHost); System.setProperty("http.proxyPort", proxyPort); } boolean switchBackProxy = ((oldProxySet != null) && (oldProxyHost != null) && (oldProxyPort != null)); // calculate new URI URI uriNew = null; try { uriNew = getNewURI(uri.getNodeValue(), baseURI); } catch (URISyntaxException ex) { throw new ResourceResolverException("generic.EmptyMessage", ex, uri, baseURI); } URL url = uriNew.toURL(); URLConnection urlConnection = url.openConnection(); { // set proxy pass String proxyUser = engineGetProperty( ResolverDirectHTTP.properties[ResolverDirectHTTP.HttpProxyUser]); String proxyPass = engineGetProperty( ResolverDirectHTTP.properties[ResolverDirectHTTP.HttpProxyPass]); if ((proxyUser != null) && (proxyPass != null)) { String password = proxyUser + ":" + proxyPass; String encodedPassword = Base64.encode(password.getBytes("ISO-8859-1")); // or was it Proxy-Authenticate ? urlConnection.setRequestProperty("Proxy-Authorization", encodedPassword); } } { // check if Basic authentication is required String auth = urlConnection.getHeaderField("WWW-Authenticate"); if (auth != null && auth.startsWith("Basic")) { // do http basic authentication String user = engineGetProperty( ResolverDirectHTTP.properties[ResolverDirectHTTP.HttpBasicUser]); String pass = engineGetProperty( ResolverDirectHTTP.properties[ResolverDirectHTTP.HttpBasicPass]); if ((user != null) && (pass != null)) { urlConnection = url.openConnection(); String password = user + ":" + pass; String encodedPassword = Base64.encode(password.getBytes("ISO-8859-1")); // set authentication property in the http header urlConnection.setRequestProperty("Authorization", "Basic " + encodedPassword); } } } String mimeType = urlConnection.getHeaderField("Content-Type"); InputStream inputStream = urlConnection.getInputStream(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte buf[] = new byte[4096]; int read = 0; int summarized = 0; while ((read = inputStream.read(buf)) >= 0) { baos.write(buf, 0, read); summarized += read; } if (log.isDebugEnabled()) { log.debug("Fetched " + summarized + " bytes from URI " + uriNew.toString()); } XMLSignatureInput result = new XMLSignatureInput(baos.toByteArray()); result.setSourceURI(uriNew.toString()); result.setMIMEType(mimeType); // switch off proxy usage if (useProxy && switchBackProxy) { System.setProperty("http.proxySet", oldProxySet); System.setProperty("http.proxyHost", oldProxyHost); System.setProperty("http.proxyPort", oldProxyPort); } return result; } catch (MalformedURLException ex) { throw new ResourceResolverException("generic.EmptyMessage", ex, uri, baseURI); } catch (IOException ex) { throw new ResourceResolverException("generic.EmptyMessage", ex, uri, baseURI); } } /** * We resolve http URIs <I>without</I> fragment... * * @param uri * @param baseURI * @return true if can be resolved */ public boolean engineCanResolve(Attr uri, String baseURI) { if (uri == null) { if (log.isDebugEnabled()) { log.debug("quick fail, uri == null"); } return false; } String uriNodeValue = uri.getNodeValue(); if (uriNodeValue.equals("") || (uriNodeValue.charAt(0) == '#')) { if (log.isDebugEnabled()) { log.debug("quick fail for empty URIs and local ones"); } return false; } if (log.isDebugEnabled()) { log.debug("I was asked whether I can resolve " + uriNodeValue); } if (uriNodeValue.startsWith("http:") || (baseURI != null && baseURI.startsWith("http:"))) { if (log.isDebugEnabled()) { log.debug("I state that I can resolve " + uriNodeValue); } return true; } if (log.isDebugEnabled()) { log.debug("I state that I can't resolve " + uriNodeValue); } return false; } /** * @inheritDoc */ public String[] engineGetPropertyKeys() { return (String[]) ResolverDirectHTTP.properties.clone(); } private static URI getNewURI(String uri, String baseURI) throws URISyntaxException { URI newUri = null; if (baseURI == null || "".equals(baseURI)) { newUri = new URI(uri); } else { newUri = new URI(baseURI).resolve(uri); } // if the URI contains a fragment, ignore it if (newUri.getFragment() != null) { URI uriNewNoFrag = new URI(newUri.getScheme(), newUri.getSchemeSpecificPart(), null); return uriNewNoFrag; } return newUri; } }