switch getMailExchangerIPs() to DNSUtil

[org.ibex.mail.git] / src / org / ibex / mail / SMTP.java

diff --git a/src/org/ibex/mail/SMTP.java b/src/org/ibex/mail/SMTP.java
index 64677a0..db5da88 100644 (file)
--- a/src/org/ibex/mail/SMTP.java
+++ b/src/org/ibex/mail/SMTP.java
@@ -11,8 +11,6 @@ import java.net.*;
 import java.io.*;
 import java.util.*;
 import java.text.*;
-import javax.naming.*;
-import javax.naming.directory.*;
 
 // FIXME: inbound throttling/ratelimiting
 
@@ -53,6 +51,8 @@ public class SMTP {
     public static final int GRAYLIST_MINWAIT =  1000 * 60 * 60;           // one hour
     public static final int GRAYLIST_MAXWAIT =  1000 * 60 * 60 * 24 * 5;  // five days
 
+    public static final int RETRY_TIME = 1000 * 60 * 30;
+
     public static final Graylist graylist;
     public static final Whitelist whitelist;
     static {
@@ -197,7 +197,8 @@ public class SMTP {
                     command = command.substring(10).trim();
                     from = command.equals("<>") ? null : new Address(command);
                     conn.println("250 " + from + " is syntactically correct");
-                    // FEATURE: perform SMTP validation on the address, reject if invalid
+                    // Don't perform SAV; discouraged here
+                    //   http://blog.fastmail.fm/2007/12/05/sending-email-servers-best-practice/
                 } else if (c.startsWith("RCPT TO:")) {
                     // some clients are broken and put RCPT first; we will tolerate this
                     command = command.substring(8).trim();
@@ -332,7 +333,7 @@ public class SMTP {
                 Log.warn(SMTP.Outgoing.class, "aieeee, null envelopeTo: " + m.summary());
                 return false;
             }
-            InetAddress[] mx = getMailExchangerIPs(m.envelopeTo.host);
+            InetAddress[] mx = DNSUtil.getMailExchangerIPs(m.envelopeTo.host);
             if (mx.length == 0) {
                if (!noBounces) {
                    enqueue(m.bounce("could not resolve " + m.envelopeTo.host));
@@ -369,14 +370,23 @@ public class SMTP {
             Connection conn = null;
             try {
                 conn = new Connection(new Socket(mx, 25), InetAddress.getLocalHost().getHostName());
+                InetAddress localAddress = conn.getSocket().getLocalAddress();
+                String reverse = DNSUtil.reverseLookup(localAddress);
+                Log.info(SMTP.Outgoing.class,
+                         "outbound connection to " + mx + " uses " + localAddress + " [reverse: " + reverse + "]");
+                InetAddress relookup = InetAddress.getByName(reverse);
+                if (!relookup.equals(localAddress))
+                    Log.error(SMTP.Outgoing.class,
+                              "Warning: local machine fails forward-confirmed-reverse; " +
+                              reverse + " resolves to " + localAddress);
                 conn.setNewline("\r\n");
                 conn.setTimeout(60 * 1000);
                 check(conn.readln(), conn);  // banner
                 try {
-                    conn.println("EHLO " + conn.vhost);
+                    conn.println("EHLO " + reverse);
                     check(conn.readln(), conn);
                 } catch (SMTPException smtpe) {
-                    conn.println("HELO " + conn.vhost);
+                    conn.println("HELO " + reverse);
                     check(conn.readln(), conn);
                 }
                 String envelopeFrom = m.envelopeFrom==null ? "" : m.envelopeFrom.toString();
@@ -444,6 +454,8 @@ public class SMTP {
         private int serial = serials++;
         private Mailbox.Iterator it;
 
+        private static Map<String,Long> nextTry = Collections.synchronizedMap(new HashMap<String,Long>());
+
         public Outgoing() {
             synchronized(Outgoing.class) {
                 threads.add(this);
@@ -468,7 +480,12 @@ public class SMTP {
                     }
                     if (!good) break;
                    try {
-                       if (attempt(it.cur())) it.delete();
+                        String messageid = it.cur().messageid;
+                        if (nextTry.get(messageid) == null || System.currentTimeMillis() > nextTry.get(messageid)) {
+                            boolean ok = attempt(it.cur());
+                            if (ok) it.delete();
+                            else nextTry.put(messageid, System.currentTimeMillis() + RETRY_TIME);
+                        }
                    } catch (Exception e) {
                        Log.error(SMTP.Outgoing.class, e);
                    }
@@ -497,42 +514,4 @@ public class SMTP {
         }
     }
 
-    public static InetAddress[] getMailExchangerIPs(String hostName) {
-        InetAddress[] ret;
-        try {
-            Hashtable env = new Hashtable();
-            env.put("java.naming.factory.initial", "com.sun.jndi.dns.DnsContextFactory");
-            DirContext ictx = new InitialDirContext(env);
-            Attributes attrs = ictx.getAttributes(hostName, new String[] { "MX" });
-            Attribute attr = attrs.get("MX");
-            if (attr == null) {
-                ret = new InetAddress[1];
-                try {
-                    ret[0] = InetAddress.getByName(hostName);
-                    if (ret[0].equals(IP.getIP(127,0,0,1)) || ret[0].isLoopbackAddress()) throw new UnknownHostException();
-                    return ret;
-                } catch (UnknownHostException uhe) {
-                    Log.warn(SMTP.class, "no MX hosts or A record for " + hostName);
-                    return new InetAddress[0];
-                }
-            } else {
-                ret = new InetAddress[attr.size()];
-                NamingEnumeration ne = attr.getAll();
-                for(int i=0; ne.hasMore();) {
-                    String mx = (String)ne.next();
-                    // FIXME we should be sorting here
-                    mx = mx.substring(mx.indexOf(" ") + 1);
-                    if (mx.charAt(mx.length() - 1) == '.') mx = mx.substring(0, mx.length() - 1);
-                    InetAddress ia = InetAddress.getByName(mx);
-                    if (ia.equals(IP.getIP(127,0,0,1)) || ia.isLoopbackAddress()) continue;
-                    ret[i++] = ia;
-                }
-            }
-        } catch (Exception e) {
-            Log.warn(SMTP.class, "couldn't find MX host for " + hostName + " due to");
-            Log.warn(SMTP.class, e);
-            return new InetAddress[0];
-        }
-        return ret;
-    }
 }