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1
21 package org.jsmtpd.plugins.dnsServices;
22
23 import java.io.IOException  ;
24 import java.net.InetAddress ;
25 import java.net.UnknownHostException ;
26 import java.util.Collections ;
27 import java.util.LinkedList ;
28 import java.util.List ;
29
30 import org.apache.commons.logging.Log;
31 import org.apache.commons.logging.LogFactory;
32 import org.jsmtpd.core.common.PluginInitException;
33 import org.jsmtpd.core.common.dnsService.IDNSResolver;
34 import org.xbill.DNS.ARecord;
35 import org.xbill.DNS.DClass;
36 import org.xbill.DNS.ExtendedResolver;
37 import org.xbill.DNS.Lookup;
38 import org.xbill.DNS.MXRecord;
39 import org.xbill.DNS.Message;
40 import org.xbill.DNS.Name;
41 import org.xbill.DNS.Record;
42 import org.xbill.DNS.ReverseMap;
43 import org.xbill.DNS.Section;
44 import org.xbill.DNS.SimpleResolver;
45 import org.xbill.DNS.Type;
46
47
51 public class DNSJavaResolver implements IDNSResolver {
52
53 private String [] dnsServers;
54 private ExtendedResolver dnsResolver = null;
55 private Log log = LogFactory.getLog(DNSJavaResolver.class);
56
57 public List <InetAddress > doMXLookup(String name) {
58 if ((name==null)||(name.indexOf(".")<=0))
59 return new LinkedList <InetAddress >();
60 List <InetAddress > singleResults;
61 singleResults = doSingleMXLookup(name);
62 return singleResults;
63 }
64
65 private List <InetAddress > doSingleMXLookup (String name) {
66 List <InetAddress > results = new LinkedList <InetAddress >();
67 List <SortableMXRecord> mxRecords = new LinkedList <SortableMXRecord>();
68 try {
69 Lookup look = new Lookup(name, Type.MX);
70 look.setResolver(dnsResolver);
71 Record[] records = look.run();
72 if (records == null)
73 return results;
74 for (int i = 0; i < records.length; i++) {
75 if (records[i] instanceof MXRecord) {
76 MXRecord mx = (MXRecord) records[i];
77 mxRecords.add(new SortableMXRecord(mx));
78 }
79 }
80 Collections.sort(mxRecords);
81 for (int i = 0; i < mxRecords.size(); i++) {
82 SortableMXRecord smx = (SortableMXRecord) mxRecords.get(i);
83 MXRecord mx = smx.getMXRecord();
84 Lookup tmp = new Lookup(mx.getTarget(), Type.A);
85 tmp.setResolver(dnsResolver);
86 Record[] partial = tmp.run();
87 if (partial != null) {
88 for (int j = 0; j < partial.length; j++) {
89 if (partial[j] instanceof ARecord) {
90 ARecord re = (ARecord) partial[j];
91 results.add(re.getAddress());
92 }
93 }
94 }
95 }
96 } catch (Exception e) {
97 log.error("resolver error: ",e);
98 }
99 return results;
100 }
101
102 public String getPluginName() {
103 return "DNSJava resolver plugin for jsmptd";
104 }
105
106 public void initPlugin() throws PluginInitException {
107 SimpleResolver[] srez = new SimpleResolver[dnsServers.length];
108 try {
109 for (int i = 0; i < dnsServers.length; i++) {
110 srez[i] = new SimpleResolver(dnsServers[i]);
111 }
112 dnsResolver = new ExtendedResolver(srez);
113 } catch (UnknownHostException e) {
114 throw new PluginInitException(e);
115 }
116 }
117
118 public void setDnsServers(String cfg) {
119 if (cfg.contains(","))
120 dnsServers = cfg.split(",");
121 else {
122 dnsServers = new String [1];
123 dnsServers[0] = cfg;
124 }
125 }
126
127 public void shutdownPlugin() {}
128
129 public boolean exists(String name) {
130 try {
131 Lookup look = new Lookup(name, Type.ANY);
132 look.setResolver(dnsResolver);
133 Record[] records = look.run();
134 if ((records == null) || (records.length == 0))
135 return false;
136 else
137 return true;
138 } catch (Exception e) {
139 log.error("error: ",e);
140 }
141 return false;
142 }
143
144 public InetAddress doLookupToIp(String name) {
145
146 return null;
147 }
148
149 public String doReverseLookup(InetAddress in) {
150 Name name = ReverseMap.fromAddress(in);
151 int type = Type.PTR;
152 int dclass = DClass.IN;
153 Record rec = Record.newRecord(name, type, dclass);
154 Message query = Message.newQuery(rec);
155 Message response;
156 try {
157 response = dnsResolver.send(query);
158 } catch (IOException e) {
159 return "";
160 }
161
162 Record[] answers = response.getSectionArray(Section.ANSWER);
163 if (answers.length == 0)
164 return "";
165 else
166 return answers[0].rdataToString();
167 }
168
169 } |
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