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* regarding copyright ownership. The ASF licenses this file *
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* "License"); you may not use this file except in compliance *
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* *
* http://www.apache.org/licenses/LICENSE-2.0 *
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* software distributed under the License is distributed on an *
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
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package org.apache.james.smtpserver;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.logger.AbstractLogEnabled;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.james.services.DNSServer;
import org.apache.james.util.mail.dsn.DSNStatus;
import org.apache.mailet.MailAddress;
import java.util.Collection;
import java.util.Locale;
import java.util.StringTokenizer;
/**
* Handles MAIL command
*/
public class MailCmdHandler
extends AbstractLogEnabled
implements CommandHandler,Configurable, Serviceable {
private final static String MAIL_OPTION_SIZE = "SIZE";
private final static String MESG_SIZE = "MESG_SIZE"; // The size of the message
private boolean checkValidSenderDomain = false;
private boolean checkAuthClients = false;
private DNSServer dnsServer = null;
/**
* @see org.apache.avalon.framework.configuration.Configurable#configure(Configuration)
*/
public void configure(Configuration handlerConfiguration) throws ConfigurationException {
Configuration configuration = handlerConfiguration.getChild("checkValidSenderDomain",false);
if(configuration != null) {
checkValidSenderDomain = configuration.getValueAsBoolean();
if (checkValidSenderDomain && dnsServer == null) {
throw new ConfigurationException("checkValidSenderDomain enabled but no DNSServer service provided to SMTPServer");
}
}
Configuration configRelay = handlerConfiguration.getChild("checkAuthClients",false);
if(configRelay != null) {
checkAuthClients = configRelay.getValueAsBoolean();
}
}
/**
* @see org.apache.avalon.framework.service.Serviceable#service(ServiceManager)
*/
public void service(ServiceManager serviceMan) throws ServiceException {
dnsServer = (DNSServer) serviceMan.lookup(DNSServer.ROLE);
}
/**
* handles MAIL command
*
* @see org.apache.james.smtpserver.CommandHandler#onCommand(SMTPSession)
*/
public void onCommand(SMTPSession session) {
doMAIL(session, session.getCommandArgument());
}
/**
* Handler method called upon receipt of a MAIL command.
* Sets up handler to deliver mail as the stated sender.
*
* @param session SMTP session object
* @param argument the argument passed in with the command by the SMTP client
*/
private void doMAIL(SMTPSession session, String argument) {
String responseString = null;
StringBuffer responseBuffer = session.getResponseBuffer();
String sender = null;
boolean badSenderDomain = false;
if ((argument != null) && (argument.indexOf(":") > 0)) {
int colonIndex = argument.indexOf(":");
sender = argument.substring(colonIndex + 1);
argument = argument.substring(0, colonIndex);
}
if (session.getState().containsKey(SMTPSession.SENDER)) {
responseString = "503 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.DELIVERY_OTHER)+" Sender already specified";
session.writeResponse(responseString);
} else if (!session.getState().containsKey(SMTPSession.CURRENT_HELO_MODE) && session.useHeloEhloEnforcement()) {
responseString = "503 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.DELIVERY_OTHER)+" Need HELO or EHLO before MAIL";
session.writeResponse(responseString);
} else if (argument == null || !argument.toUpperCase(Locale.US).equals("FROM")
|| sender == null) {
responseString = "501 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.DELIVERY_INVALID_ARG)+" Usage: MAIL FROM:<sender>";
session.writeResponse(responseString);
} else {
sender = sender.trim();
// the next gt after the first lt ... AUTH may add more <>
int lastChar = sender.indexOf('>', sender.indexOf('<'));
// Check to see if any options are present and, if so, whether they are correctly formatted
// (separated from the closing angle bracket by a ' ').
if ((lastChar > 0) && (sender.length() > lastChar + 2) && (sender.charAt(lastChar + 1) == ' ')) {
String mailOptionString = sender.substring(lastChar + 2);
// Remove the options from the sender
sender = sender.substring(0, lastChar + 1);
StringTokenizer optionTokenizer = new StringTokenizer(mailOptionString, " ");
while (optionTokenizer.hasMoreElements()) {
String mailOption = optionTokenizer.nextToken();
int equalIndex = mailOption.indexOf('=');
String mailOptionName = mailOption;
String mailOptionValue = "";
if (equalIndex > 0) {
mailOptionName = mailOption.substring(0, equalIndex).toUpperCase(Locale.US);
mailOptionValue = mailOption.substring(equalIndex + 1);
}
// Handle the SIZE extension keyword
if (mailOptionName.startsWith(MAIL_OPTION_SIZE)) {
if (!(doMailSize(session, mailOptionValue, sender))) {
return;
}
} else {
// Unexpected option attached to the Mail command
if (getLogger().isDebugEnabled()) {
StringBuffer debugBuffer =
new StringBuffer(128)
.append("MAIL command had unrecognized/unexpected option ")
.append(mailOptionName)
.append(" with value ")
.append(mailOptionValue);
getLogger().debug(debugBuffer.toString());
}
}
}
}
if (!sender.startsWith("<") || !sender.endsWith(">")) {
responseString = "501 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.ADDRESS_SYNTAX_SENDER)+" Syntax error in MAIL command";
session.writeResponse(responseString);
if (getLogger().isErrorEnabled()) {
StringBuffer errorBuffer =
new StringBuffer(128)
.append("Error parsing sender address: ")
.append(sender)
.append(": did not start and end with < >");
getLogger().error(errorBuffer.toString());
}
return;
}
MailAddress senderAddress = null;
//Remove < and >
sender = sender.substring(1, sender.length() - 1);
if (sender.length() == 0) {
//This is the <> case. Let senderAddress == null
} else {
if (sender.indexOf("@") < 0) {
sender = sender + "@localhost";
}
try {
senderAddress = new MailAddress(sender);
} catch (Exception pe) {
responseString = "501 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.ADDRESS_SYNTAX_SENDER)+" Syntax error in sender address";
session.writeResponse(responseString);
if (getLogger().isErrorEnabled()) {
StringBuffer errorBuffer =
new StringBuffer(256)
.append("Error parsing sender address: ")
.append(sender)
.append(": ")
.append(pe.getMessage());
getLogger().error(errorBuffer.toString());
}
return;
}
}
// check only if senderAddress is not null
if (checkValidSenderDomain == true && senderAddress != null) {
/**
* don't check if the ip address is allowed to relay. Only check if it is set in the config.
*/
if (checkAuthClients || !session.isRelayingAllowed()) {
// Maybe we should build a static method in org.apache.james.dnsserver.DNSServer ?
Collection records;
records = dnsServer.findMXRecords(senderAddress.getHost());
if (records == null || records.size() == 0) {
badSenderDomain = true;
}
// try to resolv the provided domain in the senderaddress. If it can not resolved do not accept it.
if (badSenderDomain) {
responseString = "501 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.ADDRESS_SYNTAX_SENDER)+ " sender " + senderAddress + " contains a domain with no valid MX records";
session.writeResponse(responseString);
getLogger().info(responseString);
}
}
}
if (!badSenderDomain) {
session.getState().put(SMTPSession.SENDER, senderAddress);
responseBuffer.append("250 "+DSNStatus.getStatus(DSNStatus.SUCCESS,DSNStatus.ADDRESS_OTHER)+" Sender <")
.append(sender)
.append("> OK");
responseString = session.clearResponseBuffer();
session.writeResponse(responseString);
}
}
}
/**
* Handles the SIZE MAIL option.
*
* @param session SMTP session object
* @param mailOptionValue the option string passed in with the SIZE option
* @param tempSender the sender specified in this mail command (for logging purpose)
* @return true if further options should be processed, false otherwise
*/
private boolean doMailSize(SMTPSession session, String mailOptionValue, String tempSender) {
int size = 0;
try {
size = Integer.parseInt(mailOptionValue);
} catch (NumberFormatException pe) {
// This is a malformed option value. We return an error
String responseString = "501 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.DELIVERY_INVALID_ARG)+" Syntactically incorrect value for SIZE parameter";
session.writeResponse(responseString);
getLogger().error("Rejected syntactically incorrect value for SIZE parameter.");
return false;
}
if (getLogger().isDebugEnabled()) {
StringBuffer debugBuffer =
new StringBuffer(128)
.append("MAIL command option SIZE received with value ")
.append(size)
.append(".");
getLogger().debug(debugBuffer.toString());
}
long maxMessageSize = session.getConfigurationData().getMaxMessageSize();
if ((maxMessageSize > 0) && (size > maxMessageSize)) {
// Let the client know that the size limit has been hit.
String responseString = "552 "+DSNStatus.getStatus(DSNStatus.PERMANENT,DSNStatus.SYSTEM_MSG_TOO_BIG)+" Message size exceeds fixed maximum message size";
session.writeResponse(responseString);
StringBuffer errorBuffer =
new StringBuffer(256)
.append("Rejected message from ")
.append(tempSender != null ? tempSender : null)
.append(" from host ")
.append(session.getRemoteHost())
.append(" (")
.append(session.getRemoteIPAddress())
.append(") of size ")
.append(size)
.append(" exceeding system maximum message size of ")
.append(maxMessageSize)
.append("based on SIZE option.");
getLogger().error(errorBuffer.toString());
return false;
} else {
// put the message size in the message state so it can be used
// later to restrict messages for user quotas, etc.
session.getState().put(MESG_SIZE, new Integer(size));
}
return true;
}
}
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