001 /****************************************************************
002 * Licensed to the Apache Software Foundation (ASF) under one *
003 * or more contributor license agreements. See the NOTICE file *
004 * distributed with this work for additional information *
005 * regarding copyright ownership. The ASF licenses this file *
006 * to you under the Apache License, Version 2.0 (the *
007 * "License"); you may not use this file except in compliance *
008 * with the License. You may obtain a copy of the License at *
009 * *
010 * http://www.apache.org/licenses/LICENSE-2.0 *
011 * *
012 * Unless required by applicable law or agreed to in writing, *
013 * software distributed under the License is distributed on an *
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
015 * KIND, either express or implied. See the License for the *
016 * specific language governing permissions and limitations *
017 * under the License. *
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019
020 package org.apache.james.protocols.smtp.core;
021
022 import java.util.ArrayList;
023 import java.util.List;
024
025 import org.apache.james.protocols.api.Request;
026 import org.apache.james.protocols.api.Response;
027 import org.apache.james.protocols.api.handler.CommandHandler;
028 import org.apache.james.protocols.api.handler.ExtensibleHandler;
029 import org.apache.james.protocols.smtp.SMTPResponse;
030 import org.apache.james.protocols.smtp.SMTPRetCode;
031 import org.apache.james.protocols.smtp.SMTPSession;
032 import org.apache.james.protocols.smtp.hook.HookResult;
033 import org.apache.james.protocols.smtp.hook.HookResultHook;
034 import org.apache.james.protocols.smtp.hook.HookReturnCode;
035
036 /**
037 * Abstract class which Handle hook-aware CommanHandler.
038 *
039 */
040 public abstract class AbstractHookableCmdHandler<Hook extends org.apache.james.protocols.smtp.hook.Hook> implements CommandHandler<SMTPSession>, ExtensibleHandler {
041
042
043 private List<Hook> hooks;
044 private List<HookResultHook> rHooks;
045
046 /**
047 * Handle command processing
048 *
049 * @see org.apache.james.protocols.api.handler.CommandHandler
050 * #onCommand(org.apache.james.protocols.api.ProtocolSession, Request)
051 */
052 public Response onCommand(SMTPSession session, Request request) {
053 String command = request.getCommand();
054 String parameters = request.getArgument();
055 SMTPResponse response = doFilterChecks(session, command, parameters);
056
057 if (response == null) {
058
059 response = processHooks(session, command, parameters);
060 if (response == null) {
061 return doCoreCmd(session, command, parameters);
062 } else {
063 return response;
064 }
065 } else {
066 return response;
067 }
068
069 }
070
071 /**
072 * Process all hooks for the given command
073 *
074 * @param session
075 * the SMTPSession object
076 * @param command
077 * the command
078 * @param parameters
079 * the paramaters
080 * @return SMTPResponse
081 */
082 private SMTPResponse processHooks(SMTPSession session, String command,
083 String parameters) {
084 List<Hook> hooks = getHooks();
085 if (hooks != null) {
086 int count = hooks.size();
087 for (int i = 0; i < count; i++) {
088 Hook rawHook = hooks.get(i);
089 session.getLogger().debug("executing hook " + rawHook.getClass().getName());
090 long start = System.currentTimeMillis();
091
092 HookResult hRes = callHook(rawHook, session, parameters);
093 long executionTime = System.currentTimeMillis() - start;
094
095 if (rHooks != null) {
096 for (int i2 = 0; i2 < rHooks.size(); i2++) {
097 Object rHook = rHooks.get(i2);
098 session.getLogger().debug("executing hook " + rHook);
099 hRes = ((HookResultHook) rHook).onHookResult(session, hRes, executionTime, rawHook);
100 }
101 }
102
103 // call the core cmd if we receive a ok return code of the hook so no other hooks are executed
104 if ((hRes.getResult() & HookReturnCode.OK) == HookReturnCode.OK) {
105 SMTPResponse response = doCoreCmd(session, command, parameters);
106 if ((hRes.getResult() & HookReturnCode.DISCONNECT) == HookReturnCode.DISCONNECT) {
107 response.setEndSession(true);
108 }
109 return response;
110 } else {
111 SMTPResponse res = calcDefaultSMTPResponse(hRes);
112 if (res != null) {
113 return res;
114 }
115 }
116 }
117 }
118 return null;
119 }
120
121 /**
122 * Must be implemented by hookable cmd handlers to make the effective call to an hook.
123 *
124 * @param rawHook the hook
125 * @param session the session
126 * @param parameters the parameters
127 * @return the HookResult, will be calculated using HookResultToSMTPResponse.
128 */
129 protected abstract HookResult callHook(Hook rawHook, SMTPSession session, String parameters);
130
131 /**
132 * Convert the HookResult to SMTPResponse using default values. Should be override for using own values
133 *
134 * @param result HookResult
135 * @return SMTPResponse
136 */
137 public static SMTPResponse calcDefaultSMTPResponse(HookResult result) {
138 if (result != null) {
139 int rCode = result.getResult();
140 String smtpRetCode = result.getSmtpRetCode();
141 String smtpDesc = result.getSmtpDescription();
142
143 if ((rCode &HookReturnCode.DENY) == HookReturnCode.DENY) {
144 if (smtpRetCode == null)
145 smtpRetCode = SMTPRetCode.TRANSACTION_FAILED;
146 if (smtpDesc == null)
147 smtpDesc = "Email rejected";
148
149 SMTPResponse response = new SMTPResponse(smtpRetCode, smtpDesc);
150 if ((rCode & HookReturnCode.DISCONNECT) == HookReturnCode.DISCONNECT) {
151 response.setEndSession(true);
152 }
153 return response;
154 } else if (rCode == HookReturnCode.DENYSOFT) {
155 if (smtpRetCode == null)
156 smtpRetCode = SMTPRetCode.LOCAL_ERROR;
157 if (smtpDesc == null)
158 smtpDesc = "Temporary problem. Please try again later";
159
160 SMTPResponse response = new SMTPResponse(smtpRetCode, smtpDesc);
161 if ((rCode & HookReturnCode.DISCONNECT) == HookReturnCode.DISCONNECT) {
162 response.setEndSession(true);
163 }
164 return response;
165 } else if ((rCode & HookReturnCode.OK) == HookReturnCode.OK) {
166 if (smtpRetCode == null)
167 smtpRetCode = SMTPRetCode.MAIL_OK;
168 if (smtpDesc == null)
169 smtpDesc = "Command accepted";
170
171 SMTPResponse response = new SMTPResponse(smtpRetCode, smtpDesc);
172 if ((rCode & HookReturnCode.DISCONNECT) == HookReturnCode.DISCONNECT) {
173 response.setEndSession(true);
174 }
175 return response;
176 } else if ((rCode & HookReturnCode.DISCONNECT) == HookReturnCode.DISCONNECT) {
177 SMTPResponse response = new SMTPResponse("");
178 response.setEndSession(true);
179 return response;
180 } else {
181 // Return null as default
182 return null;
183 }
184 } else {
185 return null;
186 }
187 }
188
189 /**
190 * Execute Syntax checks and return a SMTPResponse if a syntax error was
191 * detected, otherwise null.
192 *
193 * @param session
194 * @param command
195 * @param parameters
196 * @return smtp response if a syntax error was detected, otherwise <code>null</code>
197 */
198 protected abstract SMTPResponse doFilterChecks(SMTPSession session,
199 String command, String parameters);
200
201 /**
202 * Execute the core commandHandling.
203 *
204 * @param session
205 * @param command
206 * @param parameters
207 * @return smtp response
208 */
209 protected abstract SMTPResponse doCoreCmd(SMTPSession session,
210 String command, String parameters);
211
212
213 /**
214 * @see org.apache.james.protocols.api.handler.ExtensibleHandler#getMarkerInterfaces()
215 */
216 public List<Class<?>> getMarkerInterfaces() {
217 List<Class<?>> classes = new ArrayList<Class<?>>(2);
218 classes.add(getHookInterface());
219 classes.add(HookResultHook.class);
220 return classes;
221 }
222
223 /**
224 * Return the interface which hooks need to implement to hook in
225 *
226 * @return interface
227 */
228 protected abstract Class<Hook> getHookInterface();
229
230 /**
231 * @see org.apache.james.protocols.api.handler.ExtensibleHandler#wireExtensions(java.lang.Class,
232 * java.util.List)
233 */
234 @SuppressWarnings("unchecked")
235 public void wireExtensions(Class interfaceName, List extension) {
236 if (getHookInterface().equals(interfaceName)) {
237 this.hooks = extension;
238 } else if (HookResultHook.class.equals(interfaceName)) {
239 this.rHooks = extension;
240 }
241
242 }
243
244 /**
245 * Return a list which holds all hooks for the cmdHandler
246 *
247 * @return list containing all hooks for the cmd handler
248 */
249 protected List<Hook> getHooks() {
250 return hooks;
251 }
252
253 }