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 import org.cacert.gigi.util.SystemKeywords;
  27
  28 public abstract class EmailProvider {
  29
  30     public abstract void sendMail(String to, String subject, String message, String replyto, String toname, String fromname, String errorsto, boolean extra) throws IOException;
  31
  32     private static EmailProvider instance;
  33
  34     private X509Certificate c;
  35
  36     private PrivateKey k;
  37
  38     protected void init(Certificate c, Key k) {
  39         this.c = (X509Certificate) c;
  40         this.k = (PrivateKey) k;
  41     }
  42
  43     protected final void sendSigned(String contents, PrintWriter output) throws IOException, GeneralSecurityException {
  44         if (k == null || c == null) {
  45             output.print(contents);
  46         } else {
  47             SMIME.smime(contents, k, c, output);
  48         }
  49     }
  50
  51     public static EmailProvider getInstance() {
  52         return instance;
  53     }
  54
  55     protected static void setInstance(EmailProvider instance) {
  56         EmailProvider.instance = instance;
  57     }
  58
  59     public static void initSystem(Properties conf, Certificate cert, Key pk) {
  60         try {
  61             Class<?> c = Class.forName(conf.getProperty("emailProvider"));
  62             EmailProvider ep = (EmailProvider) c.getDeclaredConstructor(Properties.class).newInstance(conf);
  63             ep.init(cert, pk);
  64             instance = ep;
  65         } catch (ReflectiveOperationException e) {
  66             e.printStackTrace();
  67         }
  68     }
  69
  70     public static final String OK = "OK";
  71
  72     public static final String FAIL = "FAIL";
  73
  74     private static final String MAIL_P_RFC_WORD = "[A-Za-z0-9\\+\\.!#$%&'*/=?^_`|~{}-]+";
  75
  76     private static final String MAIL_P_RFC_LOCAL = MAIL_P_RFC_WORD + "(?:\\." + MAIL_P_RFC_WORD + ")*";
  77
  78     private static final String MAIL_P_RFC_LABEL = "(?!(?!xn)..--|-)(?:[A-Za-z0-9-]+)(?<!-)";
  79
  80     private static final String MAIL_P_RFC_ADDRESS = MAIL_P_RFC_LOCAL + "@(?:" + MAIL_P_RFC_LABEL + "\\.)+" + MAIL_P_RFC_LABEL + "\\.?";
  81
  82     private static final Pattern MAIL_LOCAL = Pattern.compile("^" + MAIL_P_RFC_LOCAL + "$");
  83
  84     private static final Pattern MAIL_ADDRESS = Pattern.compile("^" + MAIL_P_RFC_ADDRESS + "$");
  85
  86     public String checkEmailServer(int forUid, String address) throws IOException {
  87         if (isValidMailAddress(address)) {
  88             String[] parts = address.split("@", 2);
  89             String domain = parts[1];
  90
  91             String[] mxhosts;
  92             try {
  93                 mxhosts = DNSUtil.getMXEntries(domain);
  94             } catch (NamingException e1) {
  95                 return "MX lookup for your hostname failed.";
  96             }
  97             sortMX(mxhosts);
  98
  99             for (String host : mxhosts) {
 100                 host = host.split(" ", 2)[1];
 101                 if (host.endsWith(".")) {
 102                     host = host.substring(0, host.length() - 1);
 103                 } else {
 104                     return "Strange MX records.";
 105                 }
 106                 try (Socket s = new Socket(host, 25);
 107                         BufferedReader br0 = new BufferedReader(new InputStreamReader(s.getInputStream(), "UTF-8"));//
 108                         PrintWriter pw0 = new PrintWriter(new OutputStreamWriter(s.getOutputStream(), "UTF-8"))) {
 109                     BufferedReader br = br0;
 110                     PrintWriter pw = pw0;
 111                     String line;
 112                     if ( !SendMail.readSMTPResponse(br, 220)) {
 113                         continue;
 114                     }
 115
 116                     pw.print("EHLO " + SystemKeywords.SMTP_NAME + "\r\n");
 117                     pw.flush();
 118                     boolean starttls = false;
 119                     do {
 120                         line = br.readLine();
 121                         if (line == null) {
 122                             break;
 123                         }
 124                         starttls |= line.substring(4).equals("STARTTLS");
 125                     } while (line.startsWith("250-"));
 126                     if (line == null || !line.startsWith("250 ")) {
 127                         continue;
 128                     }
 129
 130                     if (starttls) {
 131                         pw.print("STARTTLS\r\n");
 132                         pw.flush();
 133                         if ( !SendMail.readSMTPResponse(br, 220)) {
 134                             continue;
 135                         }
 136                         Socket s1 = ((SSLSocketFactory) SSLSocketFactory.getDefault()).createSocket(s, host, 25, true);
 137                         br = new BufferedReader(new InputStreamReader(s1.getInputStream(), "UTF-8"));
 138                         pw = new PrintWriter(new OutputStreamWriter(s1.getOutputStream(), "UTF-8"));
 139                         pw.print("EHLO " + SystemKeywords.SMTP_NAME + "\r\n");
 140                         pw.flush();
 141                         if ( !SendMail.readSMTPResponse(br, 250)) {
 142                             continue;
 143                         }
 144                     }
 145
 146                     pw.print("MAIL FROM: <" + SystemKeywords.SMTP_PSEUDO_FROM + ">\r\n");
 147                     pw.flush();
 148
 149                     if ( !SendMail.readSMTPResponse(br, 250)) {
 150                         continue;
 151                     }
 152                     pw.print("RCPT TO: <" + address + ">\r\n");
 153                     pw.flush();
 154
 155                     if ( !SendMail.readSMTPResponse(br, 250)) {
 156                         continue;
 157                     }
 158                     pw.print("QUIT\r\n");
 159                     pw.flush();
 160                     if ( !SendMail.readSMTPResponse(br, 221)) {
 161                         continue;
 162                     }
 163
 164                     try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast', `status`='success'::`pingState`")) {
 165                         statmt.setString(1, address);
 166                         statmt.setString(2, line);
 167                         statmt.setInt(3, forUid);
 168                         statmt.execute();
 169                     }
 170
 171                     if (line == null || !line.startsWith("250")) {
 172                         return line;
 173                     } else {
 174                         return OK;
 175                     }
 176                 }
 177
 178             }
 179         }
 180         try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast'::`emailPingType`, `status`='failed'::`pingState`")) {
 181             statmt.setString(1, address);
 182             statmt.setString(2, "Failed to make a connection to the mail server");
 183             statmt.setInt(3, forUid);
 184             statmt.execute();
 185         }
 186         return FAIL;
 187     }
 188
 189     private static void sortMX(String[] mxhosts) {
 190         Arrays.sort(mxhosts, new Comparator<String>() {
 191
 192             @Override
 193             public int compare(String o1, String o2) {
 194                 int i1 = Integer.parseInt(o1.split(" ")[0]);
 195                 int i2 = Integer.parseInt(o2.split(" ")[0]);
 196                 return Integer.compare(i1, i2);
 197             }
 198         });
 199     }
 200
 201     public static boolean isValidMailAddress(String address) {
 202         if ( !MAIL_ADDRESS.matcher(address).matches()) {
 203             return false;
 204         }
 205
 206         String[] parts = address.split("@", 2);
 207
 208         String local = parts[0];
 209         String domain = parts[1];
 210
 211         if ( !MAIL_LOCAL.matcher(local).matches()) {
 212             return false;
 213         }
 214
 215         for (String domainPart : domain.split("\\.", -1)) {
 216             if ( !DomainAssessment.isValidDomainPart(domainPart)) {
 217                 return false;
 218             }
 219         }
 220
 221         return true;
 222     }
 223
 224 }