1/*
2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk/module-client/src/main/java/org/apache/http/impl/client/AbstractAuthenticationHandler.java $
3 * $Revision: 673450 $
4 * $Date: 2008-07-02 10:35:05 -0700 (Wed, 02 Jul 2008) $
5 *
6 * ====================================================================
7 * Licensed to the Apache Software Foundation (ASF) under one
8 * or more contributor license agreements.  See the NOTICE file
9 * distributed with this work for additional information
10 * regarding copyright ownership.  The ASF licenses this file
11 * to you under the Apache License, Version 2.0 (the
12 * "License"); you may not use this file except in compliance
13 * with the License.  You may obtain a copy of the License at
14 *
15 *   http://www.apache.org/licenses/LICENSE-2.0
16 *
17 * Unless required by applicable law or agreed to in writing,
18 * software distributed under the License is distributed on an
19 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
20 * KIND, either express or implied.  See the License for the
21 * specific language governing permissions and limitations
22 * under the License.
23 * ====================================================================
24 *
25 * This software consists of voluntary contributions made by many
26 * individuals on behalf of the Apache Software Foundation.  For more
27 * information on the Apache Software Foundation, please see
28 * <http://www.apache.org/>.
29 *
30 */
31
32package org.apache.http.impl.client;
33
34import java.util.Arrays;
35import java.util.HashMap;
36import java.util.List;
37import java.util.Locale;
38import java.util.Map;
39
40import org.apache.commons.logging.Log;
41import org.apache.commons.logging.LogFactory;
42import org.apache.http.FormattedHeader;
43import org.apache.http.Header;
44import org.apache.http.HttpResponse;
45import org.apache.http.auth.AuthScheme;
46import org.apache.http.auth.AuthSchemeRegistry;
47import org.apache.http.auth.AuthenticationException;
48import org.apache.http.auth.MalformedChallengeException;
49import org.apache.http.client.AuthenticationHandler;
50import org.apache.http.client.protocol.ClientContext;
51import org.apache.http.protocol.HTTP;
52import org.apache.http.protocol.HttpContext;
53import org.apache.http.util.CharArrayBuffer;
54
55/**
56 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
57 *
58 * @deprecated Please use {@link java.net.URL#openConnection} instead.
59 *     Please visit <a href="http://android-developers.blogspot.com/2011/09/androids-http-clients.html">this webpage</a>
60 *     for further details.
61 */
62@Deprecated
63public abstract class AbstractAuthenticationHandler implements AuthenticationHandler {
64
65    private final Log log = LogFactory.getLog(getClass());
66
67    private static final List<String> DEFAULT_SCHEME_PRIORITY = Arrays.asList(new String[] {
68            "ntlm",
69            "digest",
70            "basic"
71    });
72
73    public AbstractAuthenticationHandler() {
74        super();
75    }
76
77    protected Map<String, Header> parseChallenges(
78            final Header[] headers) throws MalformedChallengeException {
79
80        Map<String, Header> map = new HashMap<String, Header>(headers.length);
81        for (Header header : headers) {
82            CharArrayBuffer buffer;
83            int pos;
84            if (header instanceof FormattedHeader) {
85                buffer = ((FormattedHeader) header).getBuffer();
86                pos = ((FormattedHeader) header).getValuePos();
87            } else {
88                String s = header.getValue();
89                if (s == null) {
90                    throw new MalformedChallengeException("Header value is null");
91                }
92                buffer = new CharArrayBuffer(s.length());
93                buffer.append(s);
94                pos = 0;
95            }
96            while (pos < buffer.length() && HTTP.isWhitespace(buffer.charAt(pos))) {
97                pos++;
98            }
99            int beginIndex = pos;
100            while (pos < buffer.length() && !HTTP.isWhitespace(buffer.charAt(pos))) {
101                pos++;
102            }
103            int endIndex = pos;
104            String s = buffer.substring(beginIndex, endIndex);
105            map.put(s.toLowerCase(Locale.ENGLISH), header);
106        }
107        return map;
108    }
109
110    protected List<String> getAuthPreferences() {
111        return DEFAULT_SCHEME_PRIORITY;
112    }
113
114    public AuthScheme selectScheme(
115            final Map<String, Header> challenges,
116            final HttpResponse response,
117            final HttpContext context) throws AuthenticationException {
118
119        AuthSchemeRegistry registry = (AuthSchemeRegistry) context.getAttribute(
120                ClientContext.AUTHSCHEME_REGISTRY);
121        if (registry == null) {
122            throw new IllegalStateException("AuthScheme registry not set in HTTP context");
123        }
124
125        List<?> authPrefs = (List<?>) context.getAttribute(
126                ClientContext.AUTH_SCHEME_PREF);
127        if (authPrefs == null) {
128            authPrefs = getAuthPreferences();
129        }
130
131        if (this.log.isDebugEnabled()) {
132            this.log.debug("Authentication schemes in the order of preference: "
133                + authPrefs);
134        }
135
136        AuthScheme authScheme = null;
137        for (int i = 0; i < authPrefs.size(); i++) {
138            String id = (String) authPrefs.get(i);
139            Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
140
141            if (challenge != null) {
142                if (this.log.isDebugEnabled()) {
143                    this.log.debug(id + " authentication scheme selected");
144                }
145                try {
146                    authScheme = registry.getAuthScheme(id, response.getParams());
147                    break;
148                } catch (IllegalStateException e) {
149                    if (this.log.isWarnEnabled()) {
150                        this.log.warn("Authentication scheme " + id + " not supported");
151                        // Try again
152                    }
153                }
154            } else {
155                if (this.log.isDebugEnabled()) {
156                    this.log.debug("Challenge for " + id + " authentication scheme not available");
157                    // Try again
158                }
159            }
160        }
161        if (authScheme == null) {
162            // If none selected, something is wrong
163            throw new AuthenticationException(
164                "Unable to respond to any of these challenges: "
165                    + challenges);
166        }
167        return authScheme;
168    }
169
170}
171