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* 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 *
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* 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 *
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* specific language governing permissions and limitations *
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package org.apache.james.jspf.terms;
import org.apache.james.jspf.core.DNSLookupContinuation;
import org.apache.james.jspf.core.DNSRequest;
import org.apache.james.jspf.core.DNSResponse;
import org.apache.james.jspf.core.MacroExpand;
import org.apache.james.jspf.core.MacroExpandEnabled;
import org.apache.james.jspf.core.SPF1Constants;
import org.apache.james.jspf.core.SPFChecker;
import org.apache.james.jspf.core.SPFCheckerDNSResponseListener;
import org.apache.james.jspf.core.SPFSession;
import org.apache.james.jspf.core.SPFTermsRegexps;
import org.apache.james.jspf.core.exceptions.NeutralException;
import org.apache.james.jspf.core.exceptions.NoneException;
import org.apache.james.jspf.core.exceptions.PermErrorException;
import org.apache.james.jspf.core.exceptions.TempErrorException;
import org.apache.james.jspf.core.exceptions.TimeoutException;
import java.util.List;
/**
* This class represent the exp modifier
*
*/
public class ExpModifier extends GenericModifier implements MacroExpandEnabled, SPFCheckerDNSResponseListener {
private final class ExpandedExplanationChecker implements SPFChecker {
/**
* @see org.apache.james.jspf.core.SPFChecker#checkSPF(org.apache.james.jspf.core.SPFSession)
*/
public DNSLookupContinuation checkSPF(SPFSession spfData)
throws PermErrorException, NoneException,
TempErrorException, NeutralException {
try {
String exp = (String) spfData.getAttribute(ATTRIBUTE_EXPAND_EXPLANATION);
String expandedExplanation = macroExpand.expand(exp, spfData, MacroExpand.EXPLANATION);
spfData.setExplanation(expandedExplanation);
} catch (PermErrorException e) {
// ignore syntax error on explanation expansion
}
return null;
}
}
private final class ExpandedChecker implements SPFChecker {
/**
* @see org.apache.james.jspf.core.SPFChecker#checkSPF(org.apache.james.jspf.core.SPFSession)
*/
public DNSLookupContinuation checkSPF(SPFSession spfData) throws PermErrorException,
NoneException, TempErrorException, NeutralException {
String host = macroExpand.expand(getHost(), spfData, MacroExpand.DOMAIN);
return new DNSLookupContinuation(new DNSRequest(host, DNSRequest.TXT), ExpModifier.this);
}
}
private static final String ATTRIBUTE_EXPAND_EXPLANATION = "ExpModifier.ExpandExplanation";
/**
* ABNF: explanation = "exp" "=" domain-spec
*
* NOTE: the last +"?" has been added to support RFC4408 ERRATA for the EXP modifier.
* An "exp=" should not result in a perm error but should be ignored.
* Errata: http://www.openspf.org/RFC_4408/Errata#empty-exp
*
* NOTE: the last +"?" has been then removed because OpenSPF released a new testsuite
* requiring a PermError on "exp=" (see JSPF-56).
*/
public static final String REGEX = "[eE][xX][pP]" + "\\="
+ SPFTermsRegexps.DOMAIN_SPEC_REGEX;
private MacroExpand macroExpand;
private ExpandedChecker expandedChecker = new ExpandedChecker();
private ExpandedExplanationChecker expandedExplanationChecker = new ExpandedExplanationChecker();
/**
* Generate the explanation and set it in SPF1Data so it can be accessed
* easy later if needed
*
* @param spfData
* The SPF1Data which should used
* @throws PermErrorException
* @throws TempErrorException
* @throws NoneException
* @throws NeutralException
*/
protected DNSLookupContinuation checkSPFLogged(SPFSession spfData) throws PermErrorException, TempErrorException, NeutralException, NoneException {
String host = getHost();
// RFC4408 Errata: http://www.openspf.org/RFC_4408/Errata#empty-exp
if (host == null) {
return null;
}
// If we should ignore the explanation we don't have to run this class
if (spfData.ignoreExplanation() == true)
return null;
// If the currentResult is not fail we have no need to run all these
// methods!
if (spfData.getCurrentResult()== null || !spfData.getCurrentResult().equals(SPF1Constants.FAIL))
return null;
spfData.pushChecker(expandedChecker);
return macroExpand.checkExpand(host, spfData, MacroExpand.DOMAIN);
}
/**
* Get TXT records as a string
*
* @param dns The DNSService to query
* @param strServer
* The hostname for which we want to retrieve the TXT-Record
* @return String which reflect the TXT-Record
* @throws PermErrorException
* if more then one TXT-Record for explanation was found
* @throws NoneException
* @throws NeutralException
* @throws TempErrorException
* @throws TempErrorException
* if the lookup result was "TRY_AGAIN"
*/
/**
* @see org.apache.james.jspf.core.SPFCheckerDNSResponseListener#onDNSResponse(org.apache.james.jspf.core.DNSResponse, org.apache.james.jspf.core.SPFSession)
*/
public DNSLookupContinuation onDNSResponse(DNSResponse lookup, SPFSession spfData) throws PermErrorException, TempErrorException, NeutralException, NoneException {
try {
List<String> records = lookup.getResponse();
if (records == null) {
return null;
}
// See SPF-Spec 6.2
//
// If domain-spec is empty, or there are any DNS processing errors (any RCODE other than 0),
// or if no records are returned, or if more than one record is returned, or if there are syntax
// errors in the explanation string, then proceed as if no exp modifier was given.
if (records.size() > 1) {
log.debug("More then one TXT-Record found for explanation");
// Only catch the error and return null
} else {
String exp = records.get(0);
if (exp.length()>=2 && exp.charAt(0) == '"' && exp.charAt(exp.length() -1 ) == '"') {
exp = exp.substring(1, exp.length() - 1);
}
spfData.setAttribute(ATTRIBUTE_EXPAND_EXPLANATION, exp);
if ((exp != null) && (!exp.equals(""))) {
try {
spfData.pushChecker(expandedExplanationChecker);
return macroExpand.checkExpand(exp, spfData, MacroExpand.EXPLANATION);
} catch (PermErrorException e) {
// ignore syntax error on explanation expansion
}
}
}
} catch (TimeoutException e) {
// Nothing todo here.. just return null
}
return null;
}
/**
* @see java.lang.Object#toString()
*/
public String toString() {
return "exp="+getHost();
}
/**
* @see org.apache.james.jspf.core.MacroExpandEnabled#enableMacroExpand(org.apache.james.jspf.core.MacroExpand)
*/
public void enableMacroExpand(MacroExpand macroExpand) {
this.macroExpand = macroExpand;
}
}