src/org/ibex/mail/Whitelist.java

   1 package org.ibex.mail;
   2
   3 import org.ibex.io.*;
   4 import org.ibex.net.*;
   5 import org.ibex.mail.protocol.*;
   6 import org.ibex.util.*;
   7 import org.ibex.net.*;
   8 import java.sql.*;
   9 import java.net.*;
  10 import java.io.*;
  11 import java.util.*;
  12 import java.sql.Timestamp;
  13 import java.sql.Connection;
  14
  15 public class Whitelist extends SqliteDB {
  16
  17     public Whitelist(String filename) {
  18         super(filename,
  19               new String[] {
  20                   "create table if not exists 'whitelist' (email)",
  21                   "create table if not exists 'pending' (spamid,email,message,date)"
  22               },
  23               true);
  24         getTable("pending").reap("date");
  25     }
  26
  27     public boolean handleRequest(org.ibex.net.Connection c) {
  28         try {
  29             Socket sock = c.getSocket();
  30             BufferedReader br = new BufferedReader(new InputStreamReader(sock.getInputStream()));
  31             String s = br.readLine();
  32             String url = s.substring(s.indexOf(' ')+1);
  33             url = url.substring(0, url.indexOf(' '));
  34             while(s!=null && !s.equals(""))
  35                 s = br.readLine();
  36             PrintWriter pw = new PrintWriter(new OutputStreamWriter(sock.getOutputStream()));
  37             if (!url.startsWith("/whitelist/")) {
  38                 pw.print("HTTP/1.0 404 Not Found\r\n");
  39                 pw.print("Content-Type: text/plain\r\n");
  40                 pw.print("\r\n");
  41                 pw.println("you are lost.");
  42             } else {
  43                 url = url.substring("/whitelist/".length());
  44                 url = URLDecoder.decode(url);
  45                 if (url.endsWith(".txt")) url = url.substring(0, url.length()-4);
  46                 pw.print("HTTP/1.0 200 OK\r\n");
  47                 pw.print("Content-Type: text/plain\r\n");
  48                 pw.print("\r\n");
  49                 try {
  50                     SMTP.whitelist.response(url);
  51                     pw.println("Thanks!  You've been added to my list of non-spammers and your message");
  52                     pw.println("has been moved to my inbox.");
  53                     pw.println("email id " + url);
  54                     pw.println("");
  55                 } catch (Exception e) {
  56                     e.printStackTrace(pw);
  57                 }
  58             }
  59             pw.flush();
  60             sock.close();
  61         } catch (Exception e) { throw new RuntimeException(e); }
  62         return true;
  63     }
  64
  65     public synchronized boolean isWhitelisted(Address a) {
  66         try {
  67             if (a==null) return false;
  68             PreparedStatement check = conn.prepareStatement("select * from 'whitelist' where email=?");
  69             check.setString(1, a.toString(false).toLowerCase());
  70             ResultSet rs = check.executeQuery();
  71             return !rs.isAfterLast();
  72         } catch (SQLException e) { throw new RuntimeException(e); }
  73     }
  74
  75     public synchronized void addWhitelist(Address a) {
  76         try {
  77             PreparedStatement add    = conn.prepareStatement("insert or replace into 'whitelist' values(?)");
  78             add.setString(1, a.toString(false).toLowerCase());
  79             add.executeUpdate();
  80         } catch (SQLException e) { throw new RuntimeException(e); }
  81     }
  82
  83     public synchronized void response(String messageid) throws IOException, MailException {
  84         try {
  85             PreparedStatement query = conn.prepareStatement("select email,message from pending where spamid=?");
  86             query.setString(1, messageid);
  87             ResultSet rs = query.executeQuery();
  88             if (!rs.next())
  89                 throw new RuntimeException("could not find messageid \""+messageid+"\"");
  90             HashSet<Message> hsm = new HashSet<Message>();
  91             synchronized(this) {
  92                 do {
  93                     addWhitelist(Address.parse(rs.getString(1)));
  94                     Message m = Message.newMessage(new Fountain.StringFountain(rs.getString(2)));
  95                     Address a = m.headers.get("reply-to")==null ? null : Address.parse(m.headers.get("reply-to"));
  96                     if (a!=null) addWhitelist(a);
  97                     a = m.from;
  98                     if (a!=null) addWhitelist(a);
  99                     a = m.envelopeFrom;
 100                     if (a!=null) addWhitelist(a);
 101                     hsm.add(m);
 102                 } while (rs.next());
 103             }
 104             for(Message m : hsm)
 105                 Target.root.accept(m);
 106         } catch (SQLException e) { throw new RuntimeException(e); }
 107     }
 108
 109     public void challenge(Message m) {
 110         try {
 111             // FIXME: don't challenge emails with binaries in them;
 112             // reject them outright and have the sender send an
 113             // initial message w/o a binary.
 114
 115             // FIXME: use Auto here!!!
 116             // The challenge should refer to the message-id of the mail being challenged.
 117
 118             // FIXME: watch outgoing MessageID's: if something comes
 119             // back with an In-Reply-To mentioning a MessageID from
 120             // the last few days, auto-whitelist them.
 121
 122             // FIXME: important that "From" on the challenge matches
 123             // RCPT TO on the original message.
 124
 125             Log.warn(Whitelist.class, "challenging message: " + m.summary());
 126
 127             Address to = m.headers.get("reply-to")==null ? null : Address.parse(m.headers.get("reply-to"));
 128             if (to==null) to = m.from;
 129             if (to==null) to = m.envelopeFrom;
 130
 131             if (m.envelopeTo==null || m.envelopeTo.equals("null") || m.envelopeTo.equals("")) {
 132                 Log.warn(this, "message is missing a to/replyto/envelopeto header; cannot accept");
 133                 return;
 134             }
 135             if (m.headers.get("Auto-Submitted") != null &&
 136                 m.headers.get("Auto-Submitted").toLowerCase().indexOf("auto-replied")!=-1) {
 137                 Log.warn(this, "refusing to send a challenge to a message "+
 138                          "with Auto-Submitted=\""+m.headers.get("Auto-Submitted")+"\"");
 139                 return;
 140             }
 141
 142             Address from = Address.parse("adam@megacz.com");
 143
 144             String messageid = "x" + m.messageid.substring(1);
 145             messageid = messageid.substring(0, messageid.length() - 1);
 146             messageid = messageid.replace('%','_');
 147             Log.warn(Whitelist.class, "got challenge for: " + messageid);
 148
 149             String url = "http://www.megacz.com:8025/whitelist/"+URLEncoder.encode(messageid)+".txt";
 150             String message =
 151                 "Return-Path: <>"                                     + "\r\n" +
 152                 "Envelope-To: "           + to                        + "\r\n" +
 153                 "X-Originally-Received: " + m.headers.get("received") + "\r\n" +
 154                 "To: "                    + to                        + "\r\n" +
 155                 "From: "                  + from                      + "\r\n" +
 156                 "Subject: Re: "           + m.subject                 + "\r\n" +
 157                 "Message-ID:"             + Message.generateFreshMessageId() + "\r\n" +
 158                 "\r\n" +
 159                 "Hi, I've never sent a message to you before, so my spam filter trapped\n"        +
 160                 "your email.  If you're really a human being and not an evil spammer,\n"          +
 161                 "please click the link below or paste it into a web browser; doing so will\n"     +
 162                 "add you to my list of non-spammers (so you won't get this email in the future)\n"+
 163                 "and it will move your message from my spam folder to my incoming mail folder.\n" +
 164                 "\n"                                                                              +
 165                 "Thanks!\n"                                                                       +
 166                 "\n"                                                                              +
 167                 "  - Adam\n"                                                                      +
 168                 "\n"                                                                              +
 169                 url+"\n" +
 170                 "\n"                                                                              +
 171                 "\n"                                                                              +
 172                 "About this message:\n" +
 173                 "\n"                                                                              +
 174                 "NOTE: SPAMCOP DOES NOT CONSIDER THIS TO BE SPAM; see this:\n"+
 175                 "\n"+
 176                 "         http://www.spamcop.net/fom-serve/cache/369.html\n"+
 177                 "\n"+
 178                 "      and examine the \"x-originally-received\" header on this message \n"+
 179                 "      for the required \"chain of custody\" information.\n"+
 180                 "\n"+
 181                 "      Only one of these challenge messages is ever generated in response to \n"+
 182                 "      a given inbound SMTP connection; it cannot be used to amplify spam    \n"+
 183                 "      attacks, and in fact actually retards them while also stripping the   \n"+
 184                 "      advertisement they were meant to convey.\n"+
 185                 "\n"+
 186                 "      Only one delivery attempt for this challenge is ever made, and it is made\n"+
 187                 "      DURING the SMTP delivery of the message being challenged (that is, \n"+
 188                 "      between C:DATA and S:250); the deliverer of the possibly-spam message\n"+
 189                 "      must remain SMTP connected to my server during the entire process or else\n"+
 190                 "      the delivery will immediately abort.  These challenge messages are NEVER,\n"+
 191                 "      EVER queued for multiple delivery attempts\n"+
 192                 "      \n"+
 193                 "      For more information, please see:\n"+
 194                 "      \n"+
 195                 "      http://www.templetons.com/brad/spam/crgood.html\n";
 196
 197             Message challenge = Message.newMessage(new Fountain.StringFountain(message));
 198
 199             boolean send = false;
 200             synchronized(this) {
 201                 PreparedStatement query = conn.prepareStatement("select email from pending where email=?");
 202                 query.setString(1, to.toString(false));
 203                 ResultSet rs = query.executeQuery();
 204                 if (rs.next()) {
 205                     Log.warn(this, "already challenged " + to.toString(false) + "; not challenging again.");
 206                 } else {
 207                     send = true;
 208                 }
 209             }
 210
 211             if (send)
 212                 if (!SMTP.Outgoing.attempt(challenge))
 213                     throw new RuntimeException("attempted to send challenge but could not: " + m.summary());
 214
 215             synchronized(this) {
 216                 PreparedStatement add = conn.prepareStatement("insert into pending values(?,?,?,?)");
 217                 add.setString(1, messageid);
 218                 add.setString(2, to.toString(false));
 219                 add.setString(3, streamToString(m.getStream()));
 220                 add.setTimestamp(4, new Timestamp(System.currentTimeMillis()));
 221                 add.executeUpdate();
 222             }
 223         } catch (Exception e) { throw new RuntimeException(e); }
 224     }
 225
 226     private static String streamToString(Stream stream) throws Exception {
 227         StringBuffer b = new StringBuffer();
 228         for(String s = stream.readln(); s!=null; s=stream.readln())
 229             b.append(s+"\n");
 230         return b.toString();
 231     }
 232 }
 233