|
1
21 package org.jsmtpd.plugins.smtpExtension;
22
23 import java.io.BufferedWriter  ;
24 import java.io.IOException ;
25 import java.io.OutputStreamWriter ;
26 import java.util.Iterator ;
27 import java.util.List ;
28
29 import org.apache.commons.logging.Log;
30 import org.apache.commons.logging.LogFactory;
31 import org.jsmtpd.core.common.PluginInitException;
32 import org.jsmtpd.core.common.io.BareLFException;
33 import org.jsmtpd.core.common.io.InputSizeToBig;
34 import org.jsmtpd.core.common.io.commandStream.CommandStreamParser;
35 import org.jsmtpd.core.common.smtpExtension.IProtocolHandler;
36 import org.jsmtpd.core.common.smtpExtension.ISmtpExtension;
37 import org.jsmtpd.core.common.smtpExtension.SmtpExtensionException;
38 import org.jsmtpd.tools.Base64Helper;
39 import org.jsmtpd.tools.ByteArrayTool;
40
41
51 public abstract class SmtpAuthenticator implements ISmtpExtension {
52
53 private boolean requireSecuredChannel = false;
54 private Log log = LogFactory.getLog(SmtpAuthenticator.class);
55
56 protected abstract boolean performAuth(String login, byte[] password);
57
58 public boolean smtpTrigger(String command, IProtocolHandler protocol) throws SmtpExtensionException, InputSizeToBig, IOException , BareLFException {
59
60 BufferedWriter wr = new BufferedWriter (new OutputStreamWriter (protocol.getSock().getOutputStream()));
61 CommandStreamParser csp = new CommandStreamParser(protocol.getSock().getInputStream(), 512, false);
62
63 if ((command == null) || (command.length() < 8)) {
64 return false;
65 }
66
67 String tmp = command.substring(0, 4).toUpperCase();
68 if (!tmp.equals("AUTH"))
69 return false;
71 if (requireSecuredChannel && (!protocol.isSecured())) {
72 send(wr, MSG_REQUIRE_SEC_CHANNEL);
73 log.error("client wants to auth, but is not on secured channel.");
74 throw new SmtpExtensionException();
75 }
76
77 String [] args = command.split(" ");
78 if ((args == null) || (args.length < 1)) {
79 send(wr, MSG_INVALID_CMD);
80 log.error("ESMTP:AUHT> Invalid or empty command");
81 throw new SmtpExtensionException();
82 }
83
84 if ("PLAIN".equals(args[1].toUpperCase())) {
85 if ((args.length < 2) || (args[2] == null)) {
86 send(wr, MSG_INVALID_CMD);
87 log.error("ESMTP:AUHT> Invalid or empty PLAIN command");
88 throw new SmtpExtensionException();
89 }
90
91 byte[] lpData = Base64Helper.decode(args[2]);
92
93 String [] lp = parseAuthData(lpData);
94 if ((lp.length < 2) || (args[0] == null) || (args[1] == null)) {
95 send(wr, MSG_INVALID_CMD);
96 log.error("ESMTP:AUHT> Invalid or empty PLAIN command");
97 throw new SmtpExtensionException();
98 }
99
100 boolean authRes;
102 if (lp.length==2)
103 authRes=performAuth(lp[0], lp[1].getBytes());
104 else
105 authRes=performAuth(lp[1], lp[2].getBytes());
106
107 if (authRes) {
108 protocol.setRelayed(true);
109 log.info("Remote host is now relayed (PLAIN authentication successfull)");
110 protocol.setAuthContext(lp[1]); send(wr, MSG_AUTH_OK);
112 return true;
113 } else {
114 log.info("Remote host authentication failed");
115 send(wr, MSG_AUTH_FAILED);
116 throw new SmtpExtensionException();
117 }
118 }
119
120 if ("LOGIN".equals((args[1]))) {
121 send(wr, MSG_AUTH_GO_ON + " VXNlcm5hbWU6");
122 String login = csp.readLine();
123 if (login == null) {
124 log.info("LOGIN Remote host issued a null login");
125 throttle();
126 send(wr, MSG_INVALID_CMD);
127 throw new SmtpExtensionException();
128 }
129 login = new String (Base64Helper.decode(login));
130 send(wr, MSG_AUTH_GO_ON + " UGFzc3dvcmQ6");
131 String pass = csp.readLine();
132 if (pass == null) {
133 log.info("LOGIN Remote host issued a null password");
134 throttle();
135 send(wr, MSG_INVALID_CMD);
136 throw new SmtpExtensionException();
137 }
138 byte[] pw = Base64Helper.decode(pass);
139 if (performAuth(login, pw)) {
141 protocol.setRelayed(true);
142 log.info("Remote host is now relayed (LOGIN authentication successfull)");
143 protocol.setAuthContext(login);
144 send(wr, MSG_AUTH_OK);
145 return true;
146 } else {
147 log.info("Remote host authentication failed");
148 throttle();
149 send(wr, MSG_AUTH_FAILED);
150 throw new SmtpExtensionException();
151 }
152 }
153
154 throw new SmtpExtensionException();
155 }
156
157 public String getWelcome() {
158 return "AUTH PLAIN LOGIN";
159 }
160
161 public String getPluginName() {
162 return "PLAIN/LOGIN authentication SMTP Extension for Jsmtpd";
163 }
164
165 public void initPlugin() throws PluginInitException {
166 }
167
168 public void shutdownPlugin() {
169
170 }
171
172 private void send(BufferedWriter wr, String message) throws IOException {
173 wr.write(message + "\r\n");
174 wr.flush();
175 log.debug("sent " + message + "<CR><LF>");
176 }
177
178 private static final String MSG_INVALID_CMD = "500 Invalid auth command";
179 private static final String MSG_REQUIRE_SEC_CHANNEL = "538 Encryption required for requested authentication mechanism";
180 private static final String MSG_AUTH_OK = "235 OK Authenticated";
181 private static final String MSG_AUTH_FAILED = "535 authentication failed";
182 private static final String MSG_AUTH_GO_ON = "334";
183
184 public void setRequireSecuredChannel(boolean requireSecuredChannel) {
186 this.requireSecuredChannel = requireSecuredChannel;
187 }
188
189 private void throttle() {
190 log.info("Waiting 5 secs before retry");
191 Object o = new Object ();
192 synchronized (o) {
193 try {
194
195 o.wait(5000);
196 } catch (InterruptedException e) {
197 }
198 }
199 }
200
201 private String [] parseAuthData(byte[] input) {
202 List res = ByteArrayTool.split(input, ByteArrayTool.NULL);
203 String [] ret = new String [res.size()];
204 int i = 0;
205 for (Iterator iter = res.iterator(); iter.hasNext();) {
206 byte[] element = (byte[]) iter.next();
207 ret[i] = new String (element);
208 i++;
209 }
210 return ret;
211 }
212
213 public boolean smtpPreTrigger(String command, IProtocolHandler protocol) throws SmtpExtensionException, IOException , InputSizeToBig, IOException , BareLFException {
214 return false;
215 }
216 } |
Popular Tags |
Java API By Example, From Geeks To Geeks.