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.OutputStreamWriter;
   7 import java.io.PrintWriter;
   8 import java.net.Socket;
   9 import java.security.GeneralSecurityException;
  10 import java.security.Key;
  11 import java.security.PrivateKey;
  12 import java.security.cert.Certificate;
  13 import java.security.cert.X509Certificate;
  14 import java.util.Arrays;
  15 import java.util.Comparator;
  16 import java.util.Properties;
  17 import java.util.regex.Pattern;
  18
  19 import javax.naming.NamingException;
  20 import javax.net.ssl.SSLSocketFactory;
  21
  22 import org.cacert.gigi.crypto.SMIME;
  23 import org.cacert.gigi.database.GigiPreparedStatement;
  24 import org.cacert.gigi.util.DNSUtil;
  25 import org.cacert.gigi.util.DomainAssessment;
  26
  27 public abstract class EmailProvider {
  28
  29     public abstract void sendMail(String to, String subject, String message, String replyto, String toname, String fromname, String errorsto, boolean extra) throws IOException;
  30
  31     private static EmailProvider instance;
  32
  33     private X509Certificate c;
  34
  35     private PrivateKey k;
  36
  37     protected void init(Certificate c, Key k) {
  38         this.c = (X509Certificate) c;
  39         this.k = (PrivateKey) k;
  40     }
  41
  42     protected final void sendSigned(String contents, PrintWriter output) throws IOException, GeneralSecurityException {
  43         if (k == null || c == null) {
  44             output.print(contents);
  45         } else {
  46             SMIME.smime(contents, k, c, output);
  47         }
  48     }
  49
  50     public static EmailProvider getInstance() {
  51         return instance;
  52     }
  53
  54     protected static void setInstance(EmailProvider instance) {
  55         EmailProvider.instance = instance;
  56     }
  57
  58     public static void initSystem(Properties conf, Certificate cert, Key pk) {
  59         try {
  60             Class<?> c = Class.forName(conf.getProperty("emailProvider"));
  61             EmailProvider ep = (EmailProvider) c.getDeclaredConstructor(Properties.class).newInstance(conf);
  62             ep.init(cert, pk);
  63             instance = ep;
  64         } catch (ReflectiveOperationException e) {
  65             e.printStackTrace();
  66         }
  67     }
  68
  69     public static final String OK = "OK";
  70
  71     public static final String FAIL = "FAIL";
  72
  73     private static final String MAIL_P_RFC_WORD = "[A-Za-z0-9\\+\\.!#$%&'*/=?^_`|~{}-]+";
  74
  75     private static final String MAIL_P_RFC_LOCAL = MAIL_P_RFC_WORD + "(?:\\." + MAIL_P_RFC_WORD + ")*";
  76
  77     private static final String MAIL_P_RFC_LABEL = "(?!(?!xn)..--|-)(?:[A-Za-z0-9-]+)(?<!-)";
  78
  79     private static final String MAIL_P_RFC_ADDRESS = MAIL_P_RFC_LOCAL + "@(?:" + MAIL_P_RFC_LABEL + "\\.)+" + MAIL_P_RFC_LABEL + "\\.?";
  80
  81     private static final Pattern MAIL_LOCAL = Pattern.compile("^" + MAIL_P_RFC_LOCAL + "$");
  82
  83     private static final Pattern MAIL_ADDRESS = Pattern.compile("^" + MAIL_P_RFC_ADDRESS + "$");
  84
  85     public String checkEmailServer(int forUid, String address) throws IOException {
  86         if (isValidMailAddress(address)) {
  87             String[] parts = address.split("@", 2);
  88             String domain = parts[1];
  89
  90             String[] mxhosts;
  91             try {
  92                 mxhosts = DNSUtil.getMXEntries(domain);
  93             } catch (NamingException e1) {
  94                 return "MX lookup for your hostname failed.";
  95             }
  96             sortMX(mxhosts);
  97
  98             for (String host : mxhosts) {
  99                 host = host.split(" ", 2)[1];
 100                 if (host.endsWith(".")) {
 101                     host = host.substring(0, host.length() - 1);
 102                 } else {
 103                     return "Strange MX records.";
 104                 }
 105                 try (Socket s = new Socket(host, 25);
 106                         BufferedReader br0 = new BufferedReader(new InputStreamReader(s.getInputStream(), "UTF-8"));//
 107                         PrintWriter pw0 = new PrintWriter(new OutputStreamWriter(s.getOutputStream(), "UTF-8"))) {
 108                     BufferedReader br = br0;
 109                     PrintWriter pw = pw0;
 110                     String line;
 111                     if ( !SendMail.readSMTPResponse(br, 220)) {
 112                         continue;
 113                     }
 114
 115                     pw.print("EHLO www.cacert.org\r\n");
 116                     pw.flush();
 117                     boolean starttls = false;
 118                     do {
 119                         line = br.readLine();
 120                         if (line == null) {
 121                             break;
 122                         }
 123                         starttls |= line.substring(4).equals("STARTTLS");
 124                     } while (line.startsWith("250-"));
 125                     if (line == null || !line.startsWith("250 ")) {
 126                         continue;
 127                     }
 128
 129                     if (starttls) {
 130                         pw.print("STARTTLS\r\n");
 131                         pw.flush();
 132                         if ( !SendMail.readSMTPResponse(br, 220)) {
 133                             continue;
 134                         }
 135                         Socket s1 = ((SSLSocketFactory) SSLSocketFactory.getDefault()).createSocket(s, host, 25, true);
 136                         br = new BufferedReader(new InputStreamReader(s1.getInputStream(), "UTF-8"));
 137                         pw = new PrintWriter(new OutputStreamWriter(s1.getOutputStream(), "UTF-8"));
 138                         pw.print("EHLO www.cacert.org\r\n");
 139                         pw.flush();
 140                         if ( !SendMail.readSMTPResponse(br, 250)) {
 141                             continue;
 142                         }
 143                     }
 144
 145                     pw.print("MAIL FROM: <returns@cacert.org>\r\n");
 146                     pw.flush();
 147
 148                     if ( !SendMail.readSMTPResponse(br, 250)) {
 149                         continue;
 150                     }
 151                     pw.print("RCPT TO: <" + address + ">\r\n");
 152                     pw.flush();
 153
 154                     if ( !SendMail.readSMTPResponse(br, 250)) {
 155                         continue;
 156                     }
 157                     pw.print("QUIT\r\n");
 158                     pw.flush();
 159                     if ( !SendMail.readSMTPResponse(br, 221)) {
 160                         continue;
 161                     }
 162
 163                     try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast', `status`='success'::`pingState`")) {
 164                         statmt.setString(1, address);
 165                         statmt.setString(2, line);
 166                         statmt.setInt(3, forUid);
 167                         statmt.execute();
 168                     }
 169
 170                     if (line == null || !line.startsWith("250")) {
 171                         return line;
 172                     } else {
 173                         return OK;
 174                     }
 175                 }
 176
 177             }
 178         }
 179         try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast'::`emailPingType`, `status`='failed'::`pingState`")) {
 180             statmt.setString(1, address);
 181             statmt.setString(2, "Failed to make a connection to the mail server");
 182             statmt.setInt(3, forUid);
 183             statmt.execute();
 184         }
 185         return FAIL;
 186     }
 187
 188     private static void sortMX(String[] mxhosts) {
 189         Arrays.sort(mxhosts, new Comparator<String>() {
 190
 191             @Override
 192             public int compare(String o1, String o2) {
 193                 int i1 = Integer.parseInt(o1.split(" ")[0]);
 194                 int i2 = Integer.parseInt(o2.split(" ")[0]);
 195                 return Integer.compare(i1, i2);
 196             }
 197         });
 198     }
 199
 200     public static boolean isValidMailAddress(String address) {
 201         if ( !MAIL_ADDRESS.matcher(address).matches()) {
 202             return false;
 203         }
 204
 205         String[] parts = address.split("@", 2);
 206
 207         String local = parts[0];
 208         String domain = parts[1];
 209
 210         if ( !MAIL_LOCAL.matcher(local).matches()) {
 211             return false;
 212         }
 213
 214         for (String domainPart : domain.split("\\.", -1)) {
 215             if ( !DomainAssessment.isValidDomainPart(domainPart)) {
 216                 return false;
 217             }
 218         }
 219
 220         return true;
 221     }
 222
 223 }