src/club/wpia/gigi/email/EmailProvider.java

   1 package club.wpia.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 club.wpia.gigi.crypto.SMIME;
  23 import club.wpia.gigi.database.GigiPreparedStatement;
  24 import club.wpia.gigi.util.DNSUtil;
  25 import club.wpia.gigi.util.DomainAssessment;
  26 import club.wpia.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, final String address) throws IOException {
  87         if ( !isValidMailAddress(address)) {
  88             try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast'::`emailPingType`, `status`='failed'::`pingState`")) {
  89                 statmt.setString(1, address);
  90                 statmt.setString(2, "Invalid email address provided");
  91                 statmt.setInt(3, forUid);
  92                 statmt.execute();
  93             }
  94             return FAIL;
  95         }
  96
  97         String[] parts = address.split("@", 2);
  98         String domain = parts[1];
  99
 100         String[] mxhosts;
 101         try {
 102             mxhosts = DNSUtil.getMXEntries(domain);
 103         } catch (NamingException e1) {
 104             return "MX lookup for your hostname failed.";
 105         }
 106         sortMX(mxhosts);
 107
 108         for (String host : mxhosts) {
 109             host = host.split(" ", 2)[1];
 110             if (host.endsWith(".")) {
 111                 host = host.substring(0, host.length() - 1);
 112             } else {
 113                 return "Strange MX records.";
 114             }
 115
 116             class SMTPSessionHandler {
 117
 118                 public boolean detectedSTARTTLS = false;
 119
 120                 public boolean initiateSMTPSession(BufferedReader r, PrintWriter w) throws IOException {
 121                     String line;
 122
 123                     if ( !SendMail.readSMTPResponse(r, 220)) {
 124                         return false;
 125                     }
 126
 127                     w.print("EHLO " + SystemKeywords.SMTP_NAME + "\r\n");
 128                     w.flush();
 129
 130                     detectedSTARTTLS = false;
 131                     do {
 132                         line = r.readLine();
 133                         if (line == null) {
 134                             break;
 135                         }
 136                         detectedSTARTTLS |= line.substring(4).equals("STARTTLS");
 137                     } while (line.startsWith("250-"));
 138
 139                     if (line == null || !line.startsWith("250 ")) {
 140                         return false;
 141                     }
 142
 143                     return true;
 144                 }
 145
 146                 public boolean trySendEmail(BufferedReader r, PrintWriter w) throws IOException {
 147                     w.print("MAIL FROM: <" + SystemKeywords.SMTP_PSEUDO_FROM + ">\r\n");
 148                     w.flush();
 149
 150                     if ( !SendMail.readSMTPResponse(r, 250)) {
 151                         return false;
 152                     }
 153
 154                     w.print("RCPT TO: <" + address + ">\r\n");
 155                     w.flush();
 156
 157                     if ( !SendMail.readSMTPResponse(r, 250)) {
 158                         return false;
 159                     }
 160
 161                     w.print("QUIT\r\n");
 162                     w.flush();
 163
 164                     if ( !SendMail.readSMTPResponse(r, 221)) {
 165                         return false;
 166                     }
 167
 168                     return true;
 169                 }
 170
 171             }
 172
 173             SMTPSessionHandler sh = new SMTPSessionHandler();
 174
 175             try (Socket plainSocket = new Socket(host, 25); //
 176                     BufferedReader plainReader = new BufferedReader(new InputStreamReader(plainSocket.getInputStream(), "UTF-8")); //
 177                     PrintWriter plainWriter = new PrintWriter(new OutputStreamWriter(plainSocket.getOutputStream(), "UTF-8"))) {
 178
 179                 if ( !sh.initiateSMTPSession(plainReader, plainWriter)) {
 180                     continue;
 181                 }
 182
 183                 boolean canSend = false;
 184
 185                 if (sh.detectedSTARTTLS) {
 186                     plainWriter.print("STARTTLS\r\n");
 187                     plainWriter.flush();
 188
 189                     if ( !SendMail.readSMTPResponse(plainReader, 220)) {
 190                         continue;
 191                     }
 192
 193                     try (Socket tlsSocket = ((SSLSocketFactory) SSLSocketFactory.getDefault()).createSocket(plainSocket, host, 25, true); //
 194                             BufferedReader tlsReader = new BufferedReader(new InputStreamReader(tlsSocket.getInputStream(), "UTF-8")); //
 195                             PrintWriter tlsWriter = new PrintWriter(new OutputStreamWriter(tlsSocket.getOutputStream(), "UTF-8"))) {
 196
 197                         tlsWriter.print("EHLO " + SystemKeywords.SMTP_NAME + "\r\n");
 198                         tlsWriter.flush();
 199
 200                         if ( !SendMail.readSMTPResponse(tlsReader, 250)) {
 201                             continue;
 202                         }
 203
 204                         canSend = sh.trySendEmail(tlsReader, tlsWriter);
 205                     }
 206                 } else {
 207                     canSend = sh.trySendEmail(plainReader, plainWriter);
 208                 }
 209
 210                 if ( !canSend) {
 211                     continue;
 212                 }
 213
 214                 try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast', `status`='success'::`pingState`")) {
 215                     statmt.setString(1, address);
 216                     statmt.setString(2, OK);
 217                     statmt.setInt(3, forUid);
 218                     statmt.execute();
 219                 }
 220
 221                 return OK;
 222             }
 223         }
 224
 225         try (GigiPreparedStatement statmt = new GigiPreparedStatement("INSERT INTO `emailPinglog` SET `when`=NOW(), `email`=?, `result`=?, `uid`=?, `type`='fast'::`emailPingType`, `status`='failed'::`pingState`")) {
 226             statmt.setString(1, address);
 227             statmt.setString(2, "Failed to make a connection to the mail server");
 228             statmt.setInt(3, forUid);
 229             statmt.execute();
 230         }
 231
 232         return FAIL;
 233     }
 234
 235     private static void sortMX(String[] mxhosts) {
 236         Arrays.sort(mxhosts, new Comparator<String>() {
 237
 238             @Override
 239             public int compare(String o1, String o2) {
 240                 int i1 = Integer.parseInt(o1.split(" ")[0]);
 241                 int i2 = Integer.parseInt(o2.split(" ")[0]);
 242                 return Integer.compare(i1, i2);
 243             }
 244         });
 245     }
 246
 247     public static boolean isValidMailAddress(String address) {
 248         if ( !MAIL_ADDRESS.matcher(address).matches()) {
 249             return false;
 250         }
 251
 252         String[] parts = address.split("@", 2);
 253
 254         String local = parts[0];
 255         String domain = parts[1];
 256
 257         if ( !MAIL_LOCAL.matcher(local).matches()) {
 258             return false;
 259         }
 260
 261         for (String domainPart : domain.split("\\.", -1)) {
 262             if ( !DomainAssessment.isValidDomainPart(domainPart)) {
 263                 return false;
 264             }
 265         }
 266
 267         return true;
 268     }
 269
 270 }