src/org/cacert/gigi/email/EmailProvider.java

   1 package org.cacert.gigi.email;
   2
   3 import java.io.BufferedReader;
   4 import java.io.IOException;
   5 import java.io.InputStreamReader;
   6 import java.io.PrintWriter;
   7 import java.net.Socket;
   8 import java.security.GeneralSecurityException;
   9 import java.security.Key;
  10 import java.security.PrivateKey;
  11 import java.security.cert.Certificate;
  12 import java.security.cert.X509Certificate;
  13 import java.util.Properties;
  14 import java.util.regex.Pattern;
  15
  16 import javax.naming.NamingException;
  17
  18 import org.cacert.gigi.crypto.SMIME;
  19 import org.cacert.gigi.database.DatabaseConnection;
  20 import org.cacert.gigi.database.GigiPreparedStatement;
  21 import org.cacert.gigi.util.DNSUtil;
  22
  23 public abstract class EmailProvider {
  24
  25     public abstract void sendmail(String to, String subject, String message, String from, String replyto, String toname, String fromname, String errorsto, boolean extra) throws IOException;
  26
  27     private static EmailProvider instance;
  28
  29     private X509Certificate c;
  30
  31     private PrivateKey k;
  32
  33     protected final void init(Certificate c, Key k) {
  34         this.c = (X509Certificate) c;
  35         this.k = (PrivateKey) k;
  36     }
  37
  38     protected final void sendSigned(String contents, PrintWriter output) throws IOException, GeneralSecurityException {
  39         SMIME.smime(contents, k, c, output);
  40     }
  41
  42     public static EmailProvider getInstance() {
  43         return instance;
  44     }
  45
  46     protected static void setInstance(EmailProvider instance) {
  47         EmailProvider.instance = instance;
  48     }
  49
  50     public static void initSystem(Properties conf, Certificate cert, Key pk) {
  51         try {
  52             Class<?> c = Class.forName(conf.getProperty("emailProvider"));
  53             EmailProvider ep = (EmailProvider) c.getDeclaredConstructor(Properties.class).newInstance(conf);
  54             ep.init(cert, pk);
  55             instance = ep;
  56         } catch (ReflectiveOperationException e) {
  57             e.printStackTrace();
  58         }
  59     }
  60
  61     public static final String OK = "OK";
  62
  63     public static final String FAIL = "FAIL";
  64
  65     public static final Pattern MAIL = Pattern.compile("^([a-zA-Z0-9])+([a-zA-Z0-9\\+\\._-])*@([a-zA-Z0-9_-])+([a-zA-Z0-9\\._-]+)+$");
  66
  67     public String checkEmailServer(int forUid, String address) throws IOException {
  68         if (MAIL.matcher(address).matches()) {
  69             String[] parts = address.split("@", 2);
  70             String domain = parts[1];
  71
  72             String[] mxhosts;
  73             try {
  74                 mxhosts = DNSUtil.getMXEntries(domain);
  75             } catch (NamingException e1) {
  76                 return "MX lookup for your hostname failed.";
  77             }
  78
  79             for (String host : mxhosts) {
  80                 host = host.split(" ", 2)[1];
  81                 if (host.endsWith(".")) {
  82                     host = host.substring(0, host.length() - 1);
  83                 } else {
  84                     return "Strange MX records.";
  85                 }
  86                 try (Socket s = new Socket(host, 25); BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream())); PrintWriter pw = new PrintWriter(s.getOutputStream())) {
  87                     String line;
  88                     while ((line = br.readLine()) != null && line.startsWith("220-")) {
  89                     }
  90                     if (line == null || !line.startsWith("220")) {
  91                         continue;
  92                     }
  93
  94                     pw.print("HELO www.cacert.org\r\n");
  95                     pw.flush();
  96
  97                     while ((line = br.readLine()) != null && line.startsWith("220")) {
  98                     }
  99
 100                     if (line == null || !line.startsWith("250")) {
 101                         continue;
 102                     }
 103                     pw.print("MAIL FROM: <returns@cacert.org>\r\n");
 104                     pw.flush();
 105
 106                     line = br.readLine();
 107
 108                     if (line == null || !line.startsWith("250")) {
 109                         continue;
 110                     }
 111                     pw.print("RCPT TO: <" + address + ">\r\n");
 112                     pw.flush();
 113
 114                     line = br.readLine();
 115                     pw.print("QUIT\r\n");
 116                     pw.flush();
 117
 118                     GigiPreparedStatement statmt = DatabaseConnection.getInstance().prepare("insert into `emailPinglog` set `when`=NOW(), `email`=?, `result`=?, `uid`=?");
 119                     statmt.setString(1, address);
 120                     statmt.setString(2, line);
 121                     statmt.setInt(3, forUid);
 122                     statmt.execute();
 123
 124                     if (line == null || !line.startsWith("250")) {
 125                         return line;
 126                     } else {
 127                         return OK;
 128                     }
 129                 }
 130
 131             }
 132         }
 133         GigiPreparedStatement statmt = DatabaseConnection.getInstance().prepare("insert into `emailPinglog` set `when`=NOW(), `email`=?, `result`=?, `uid`=?");
 134         statmt.setString(1, address);
 135         statmt.setString(2, "Failed to make a connection to the mail server");
 136         statmt.setInt(3, forUid);
 137         statmt.execute();
 138         return FAIL;
 139     }
 140
 141 }