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 SqliteTable {
  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               "pending",
  25               "date");
  26     }
  27
  28     public boolean handleRequest(org.ibex.net.Connection c) {
  29         try {
  30             Socket sock = c.getSocket();
  31             BufferedReader br = new BufferedReader(new InputStreamReader(sock.getInputStream()));
  32             String s = br.readLine();
  33             String url = s.substring(s.indexOf(' ')+1);
  34             url = url.substring(0, url.indexOf(' '));
  35             while(s!=null && !s.equals(""))
  36                 s = br.readLine();
  37             PrintWriter pw = new PrintWriter(new OutputStreamWriter(sock.getOutputStream()));
  38             if (!url.startsWith("/whitelist/")) {
  39                 pw.print("HTTP/1.0 404 Not Found\r\n");
  40                 pw.print("Content-Type: text/plain\r\n");
  41                 pw.print("\r\n");
  42                 pw.println("you are lost.");
  43             } else {
  44                 url = url.substring("/whitelist/".length());
  45                 url = URLDecoder.decode(url);
  46                 if (url.endsWith(".txt")) url = url.substring(0, url.length()-4);
  47                 pw.print("HTTP/1.0 200 OK\r\n");
  48                 pw.print("Content-Type: text/plain\r\n");
  49                 pw.print("\r\n");
  50                 try {
  51                     SMTP.whitelist.response(url);
  52                     pw.println("Thanks!  You've been added to my list of non-spammers and your message");
  53                     pw.println("has been moved to my inbox.");
  54                     pw.println("email id " + url);
  55                     pw.println("");
  56                 } catch (Exception e) {
  57                     e.printStackTrace(pw);
  58                 }
  59             }
  60             pw.flush();
  61             sock.close();
  62         } catch (Exception e) { throw new RuntimeException(e); }
  63         return true;
  64     }
  65
  66     public synchronized boolean isWhitelisted(Address a) {
  67         try {
  68             if (a==null) return false;
  69             PreparedStatement check = conn.prepareStatement("select * from 'whitelist' where email=?");
  70             check.setString(1, a.toString(false).toLowerCase());
  71             ResultSet rs = check.executeQuery();
  72             return !rs.isAfterLast();
  73         } catch (SQLException e) { throw new RuntimeException(e); }
  74     }
  75
  76     public synchronized void addWhitelist(Address a) {
  77         try {
  78             PreparedStatement add    = conn.prepareStatement("insert or replace into 'whitelist' values(?)");
  79             add.setString(1, a.toString(false).toLowerCase());
  80             add.executeUpdate();
  81         } catch (SQLException e) { throw new RuntimeException(e); }
  82     }
  83
  84     public synchronized void response(String messageid) throws IOException, MailException {
  85         try {
  86             PreparedStatement query = conn.prepareStatement("select email,message from pending where spamid=?");
  87             query.setString(1, messageid);
  88             ResultSet rs = query.executeQuery();
  89             if (!rs.next())
  90                 throw new RuntimeException("could not find messageid \""+messageid+"\"");
  91             HashSet<Message> hsm = new HashSet<Message>();
  92             synchronized(this) {
  93                 do {
  94                     addWhitelist(Address.parse(rs.getString(1)));
  95                     Message m = Message.newMessage(new Fountain.StringFountain(rs.getString(2)));
  96                     Address a = m.headers.get("reply-to")==null ? null : Address.parse(m.headers.get("reply-to"));
  97                     if (a!=null) addWhitelist(a);
  98                     a = m.from;
  99                     if (a!=null) addWhitelist(a);
 100                     a = m.envelopeFrom;
 101                     if (a!=null) addWhitelist(a);
 102                     hsm.add(m);
 103                 } while (rs.next());
 104             }
 105             for(Message m : hsm)
 106                 Target.root.accept(m);
 107         } catch (SQLException e) { throw new RuntimeException(e); }
 108     }
 109
 110     public void challenge(Message m) {
 111         try {
 112             // FIXME: don't challenge emails with binaries in them;
 113             // reject them outright and have the sender send an
 114             // initial message w/o a binary.
 115
 116             // FIXME: use Auto here!!!
 117             // The challenge should refer to the message-id of the mail being challenged.
 118
 119             // FIXME: watch outgoing MessageID's: if something comes
 120             // back with an In-Reply-To mentioning a MessageID from
 121             // the last few days, auto-whitelist them.
 122
 123             // FIXME: important that "From" on the challenge matches
 124             // RCPT TO on the original message.
 125
 126             Log.warn(Whitelist.class, "challenging message: " + m.summary());
 127
 128             Address to = m.headers.get("reply-to")==null ? null : Address.parse(m.headers.get("reply-to"));
 129             if (to==null) to = m.from;
 130             if (to==null) to = m.envelopeFrom;
 131
 132             if (m.envelopeTo==null || m.envelopeTo.equals("null") || m.envelopeTo.equals("")) {
 133                 Log.warn(this, "message is missing a to/replyto/envelopeto header; cannot accept");
 134                 return;
 135             }
 136             if (m.headers.get("Auto-Submitted") != null &&
 137                 m.headers.get("Auto-Submitted").toLowerCase().indexOf("auto-replied")!=-1) {
 138                 Log.warn(this, "refusing to send a challenge to a message "+
 139                          "with Auto-Submitted=\""+m.headers.get("Auto-Submitted")+"\"");
 140                 return;
 141             }
 142
 143             Address from = Address.parse("adam@megacz.com");
 144
 145             String messageid = "x" + m.messageid.substring(1);
 146             messageid = messageid.substring(0, messageid.length() - 1);
 147             messageid = messageid.replace('%','_');
 148             Log.warn(Whitelist.class, "got challenge for: " + messageid);
 149
 150             String url = "http://www.megacz.com:8025/whitelist/"+URLEncoder.encode(messageid)+".txt";
 151             String message =
 152                 "Return-Path: <>"                                     + "\r\n" +
 153                 "Envelope-To: "           + to                        + "\r\n" +
 154                 "X-Originally-Received: " + m.headers.get("received") + "\r\n" +
 155                 "To: "                    + to                        + "\r\n" +
 156                 "From: "                  + from                      + "\r\n" +
 157                 "Subject: Re: "           + m.subject                 + "\r\n" +
 158                 "Message-ID:"             + Message.generateFreshMessageId() + "\r\n" +
 159                 "\r\n" +
 160                 "Hi, I've never sent a message to you before, so my spam filter trapped\n"        +
 161                 "your email.  If you're really a human being and not an evil spammer,\n"          +
 162                 "please click the link below or paste it into a web browser; doing so will\n"     +
 163                 "add you to my list of non-spammers (so you won't get this email in the future)\n"+
 164                 "and it will move your message from my spam folder to my incoming mail folder.\n" +
 165                 "\n"                                                                              +
 166                 "Thanks!\n"                                                                       +
 167                 "\n"                                                                              +
 168                 "  - Adam\n"                                                                      +
 169                 "\n"                                                                              +
 170                 url+"\n" +
 171                 "\n"                                                                              +
 172                 "\n"                                                                              +
 173                 "About this message:\n" +
 174                 "\n"                                                                              +
 175                 "NOTE: SPAMCOP DOES NOT CONSIDER THIS TO BE SPAM; see this:\n"+
 176                 "\n"+
 177                 "         http://www.spamcop.net/fom-serve/cache/369.html\n"+
 178                 "\n"+
 179                 "      and examine the \"x-originally-received\" header on this message \n"+
 180                 "      for the required \"chain of custody\" information.\n"+
 181                 "\n"+
 182                 "      Only one of these challenge messages is ever generated in response to \n"+
 183                 "      a given inbound SMTP connection; it cannot be used to amplify spam    \n"+
 184                 "      attacks, and in fact actually retards them while also stripping the   \n"+
 185                 "      advertisement they were meant to convey.\n"+
 186                 "\n"+
 187                 "      Only one delivery attempt for this challenge is ever made, and it is made\n"+
 188                 "      DURING the SMTP delivery of the message being challenged (that is, \n"+
 189                 "      between C:DATA and S:250); the deliverer of the possibly-spam message\n"+
 190                 "      must remain SMTP connected to my server during the entire process or else\n"+
 191                 "      the delivery will immediately abort.  These challenge messages are NEVER,\n"+
 192                 "      EVER queued for multiple delivery attempts\n"+
 193                 "      \n"+
 194                 "      For more information, please see:\n"+
 195                 "      \n"+
 196                 "      http://www.templetons.com/brad/spam/crgood.html\n";
 197
 198             Message challenge = Message.newMessage(new Fountain.StringFountain(message));
 199
 200             boolean send = false;
 201             synchronized(this) {
 202                 PreparedStatement query = conn.prepareStatement("select email from pending where email=?");
 203                 query.setString(1, to.toString(false));
 204                 ResultSet rs = query.executeQuery();
 205                 if (rs.next()) {
 206                     Log.warn(this, "already challenged " + to.toString(false) + "; not challenging again.");
 207                 } else {
 208                     send = true;
 209                 }
 210             }
 211
 212             if (send)
 213                 if (!SMTP.Outgoing.attempt(challenge))
 214                     throw new RuntimeException("attempted to send challenge but could not: " + m.summary());
 215
 216             synchronized(this) {
 217                 PreparedStatement add = conn.prepareStatement("insert into pending values(?,?,?,?)");
 218                 add.setString(1, messageid);
 219                 add.setString(2, to.toString(false));
 220                 add.setString(3, streamToString(m.getStream()));
 221                 add.setTimestamp(4, new Timestamp(System.currentTimeMillis()));
 222                 add.executeUpdate();
 223             }
 224         } catch (Exception e) { throw new RuntimeException(e); }
 225     }
 226
 227     private static String streamToString(Stream stream) throws Exception {
 228         StringBuffer b = new StringBuffer();
 229         for(String s = stream.readln(); s!=null; s=stream.readln())
 230             b.append(s+"\n");
 231         return b.toString();
 232     }
 233 }
 234