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.Arrays;
  14 import java.util.Comparator;
  15 import java.util.Properties;
  16 import java.util.regex.Pattern;
  17
  18 import javax.naming.NamingException;
  19 import javax.net.ssl.SSLSocketFactory;
  20
  21 import org.cacert.gigi.crypto.SMIME;
  22 import org.cacert.gigi.database.DatabaseConnection;
  23 import org.cacert.gigi.database.GigiPreparedStatement;
  24 import org.cacert.gigi.util.DNSUtil;
  25
  26 public abstract class EmailProvider {
  27
  28     public abstract void sendmail(String to, String subject, String message, String from, String replyto, String toname, String fromname, String errorsto, boolean extra) throws IOException;
  29
  30     private static EmailProvider instance;
  31
  32     private X509Certificate c;
  33
  34     private PrivateKey k;
  35
  36     protected final void init(Certificate c, Key k) {
  37         this.c = (X509Certificate) c;
  38         this.k = (PrivateKey) k;
  39     }
  40
  41     protected final void sendSigned(String contents, PrintWriter output) throws IOException, GeneralSecurityException {
  42         SMIME.smime(contents, k, c, output);
  43     }
  44
  45     public static EmailProvider getInstance() {
  46         return instance;
  47     }
  48
  49     protected static void setInstance(EmailProvider instance) {
  50         EmailProvider.instance = instance;
  51     }
  52
  53     public static void initSystem(Properties conf, Certificate cert, Key pk) {
  54         try {
  55             Class<?> c = Class.forName(conf.getProperty("emailProvider"));
  56             EmailProvider ep = (EmailProvider) c.getDeclaredConstructor(Properties.class).newInstance(conf);
  57             ep.init(cert, pk);
  58             instance = ep;
  59         } catch (ReflectiveOperationException e) {
  60             e.printStackTrace();
  61         }
  62     }
  63
  64     public static final String OK = "OK";
  65
  66     public static final String FAIL = "FAIL";
  67
  68     public static final Pattern MAIL = Pattern.compile("^([a-zA-Z0-9])+([a-zA-Z0-9\\+\\._-])*@([a-zA-Z0-9_-])+([a-zA-Z0-9\\._-]+)+$");
  69
  70     public String checkEmailServer(int forUid, String address) throws IOException {
  71         if (MAIL.matcher(address).matches()) {
  72             String[] parts = address.split("@", 2);
  73             String domain = parts[1];
  74
  75             String[] mxhosts;
  76             try {
  77                 mxhosts = DNSUtil.getMXEntries(domain);
  78             } catch (NamingException e1) {
  79                 return "MX lookup for your hostname failed.";
  80             }
  81             sortMX(mxhosts);
  82
  83             for (String host : mxhosts) {
  84                 host = host.split(" ", 2)[1];
  85                 if (host.endsWith(".")) {
  86                     host = host.substring(0, host.length() - 1);
  87                 } else {
  88                     return "Strange MX records.";
  89                 }
  90                 try (Socket s = new Socket(host, 25); BufferedReader br0 = new BufferedReader(new InputStreamReader(s.getInputStream(), "UTF-8")); PrintWriter pw0 = new PrintWriter(s.getOutputStream())) {
  91                     BufferedReader br = br0;
  92                     PrintWriter pw = pw0;
  93                     String line;
  94                     if ( !Sendmail.readSMTPResponse(br, 220)) {
  95                         continue;
  96                     }
  97
  98                     pw.print("EHLO www.cacert.org\r\n");
  99                     pw.flush();
 100                     boolean starttls = false;
 101                     do {
 102                         line = br.readLine();
 103                         if (line == null) {
 104                             break;
 105                         }
 106                         starttls |= line.substring(4).equals("STARTTLS");
 107                     } while (line.startsWith("250-"));
 108                     if (line == null || !line.startsWith("250 ")) {
 109                         continue;
 110                     }
 111
 112                     if (starttls) {
 113                         pw.print("STARTTLS\r\n");
 114                         pw.flush();
 115                         if ( !Sendmail.readSMTPResponse(br, 220)) {
 116                             continue;
 117                         }
 118                         Socket s1 = ((SSLSocketFactory) SSLSocketFactory.getDefault()).createSocket(s, host, 25, true);
 119                         br = new BufferedReader(new InputStreamReader(s1.getInputStream(), "UTF-8"));
 120                         pw = new PrintWriter(s1.getOutputStream());
 121                         pw.print("EHLO www.cacert.org\r\n");
 122                         pw.flush();
 123                         if ( !Sendmail.readSMTPResponse(br, 250)) {
 124                             continue;
 125                         }
 126                     }
 127
 128                     pw.print("MAIL FROM: <returns@cacert.org>\r\n");
 129                     pw.flush();
 130
 131                     if ( !Sendmail.readSMTPResponse(br, 250)) {
 132                         continue;
 133                     }
 134                     pw.print("RCPT TO: <" + address + ">\r\n");
 135                     pw.flush();
 136
 137                     if ( !Sendmail.readSMTPResponse(br, 250)) {
 138                         continue;
 139                     }
 140                     pw.print("QUIT\r\n");
 141                     pw.flush();
 142                     if ( !Sendmail.readSMTPResponse(br, 221)) {
 143                         continue;
 144                     }
 145
 146                     GigiPreparedStatement statmt = DatabaseConnection.getInstance().prepare("insert into `emailPinglog` set `when`=NOW(), `email`=?, `result`=?, `uid`=?");
 147                     statmt.setString(1, address);
 148                     statmt.setString(2, line);
 149                     statmt.setInt(3, forUid);
 150                     statmt.execute();
 151
 152                     if (line == null || !line.startsWith("250")) {
 153                         return line;
 154                     } else {
 155                         return OK;
 156                     }
 157                 }
 158
 159             }
 160         }
 161         GigiPreparedStatement statmt = DatabaseConnection.getInstance().prepare("insert into `emailPinglog` set `when`=NOW(), `email`=?, `result`=?, `uid`=?");
 162         statmt.setString(1, address);
 163         statmt.setString(2, "Failed to make a connection to the mail server");
 164         statmt.setInt(3, forUid);
 165         statmt.execute();
 166         return FAIL;
 167     }
 168
 169     private static void sortMX(String[] mxhosts) {
 170         Arrays.sort(mxhosts, new Comparator<String>() {
 171
 172             @Override
 173             public int compare(String o1, String o2) {
 174                 int i1 = Integer.parseInt(o1.split(" ")[0]);
 175                 int i2 = Integer.parseInt(o2.split(" ")[0]);
 176                 return Integer.compare(i1, i2);
 177             }
 178         });
 179     }
 180
 181 }