[server] SMTP Mailing

1 files changed, 191 insertions, 0 deletions

diff --git a/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/mail/SmtpMailer.java b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/mail/SmtpMailer.java
new file mode 100644
index 00000000..4f1b415e
--- /dev/null
+++ b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/mail/SmtpMailer.java
@@ -0,0 +1,191 @@
+package org.openslx.bwlp.sat.mail;
+
+import java.io.IOException;
+import java.io.Writer;
+import java.net.InetAddress;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.spec.InvalidKeySpecException;
+
+import javax.security.auth.login.LoginException;
+
+import org.apache.commons.net.PrintCommandListener;
+import org.apache.commons.net.ProtocolCommandEvent;
+import org.apache.commons.net.ProtocolCommandListener;
+import org.apache.commons.net.smtp.AuthenticatingSMTPClient;
+import org.apache.commons.net.smtp.AuthenticatingSMTPClient.AUTH_METHOD;
+import org.apache.commons.net.smtp.SMTPReply;
+import org.apache.commons.net.smtp.SimpleSMTPHeader;
+import org.apache.log4j.Logger;
+import org.openslx.bwlp.sat.util.Util;
+
+public class SmtpMailer {
+
+	// TODO Logging
+	private static final Logger LOGGER = Logger.getLogger(SmtpMailer.class);
+
+	public enum EncryptionMode {
+		NONE,
+		IMPLICIT,
+		EXPLICIT
+	}
+
+	private final String fromAddress;
+	private final String fromName;
+	private final String replyTo;
+	private final AuthenticatingSMTPClient client;
+
+	public SmtpMailer(String host, int port, EncryptionMode ssl, String fromAddress, String fromName,
+			String replyTo, String username, String password) throws UnknownHostException, SocketException,
+			IOException, LoginException, InvalidKeyException, NoSuchAlgorithmException,
+			InvalidKeySpecException {
+		InetAddress[] ips = InetAddress.getAllByName(host);
+		if (ips == null || ips.length == 0)
+			throw new UnknownHostException(host);
+		LOGGER.debug("Mailing via " + host + ", " + ssl);
+		if (ssl == EncryptionMode.EXPLICIT || ssl == EncryptionMode.NONE) {
+			client = new AuthenticatingSMTPClient("TLSv1.2", false, "UTF-8");
+		} else {
+			client = new AuthenticatingSMTPClient("TLSv1.2", true, "UTF-8");
+		}
+		boolean cleanup = true;
+		try {
+			new ProtocolCommandListener() {
+
+				@Override
+				public void protocolReplyReceived(ProtocolCommandEvent event) {
+					event.getMessage();
+				}
+
+				@Override
+				public void protocolCommandSent(ProtocolCommandEvent event) {
+					// TODO Auto-generated method stub
+
+				}
+			};
+			client.addProtocolCommandListener(new PrintCommandListener(System.out));
+			client.setConnectTimeout(5000);
+			IOException conEx = null;
+			for (InetAddress ip : ips) {
+				try {
+					client.connect(ip, port);
+					if (!SMTPReply.isPositiveCompletion(client.getReplyCode())) {
+						client.disconnect();
+						continue;
+					}
+					conEx = null;
+					break;
+				} catch (IOException e) {
+					conEx = e;
+				}
+			}
+			if (conEx != null)
+				throw conEx;
+			if (!client.elogin("bwlehrpool.sat")) {
+				throw new LoginException("SMTP server rejected EHLO");
+			}
+			if (ssl == EncryptionMode.EXPLICIT && !client.execTLS()) {
+				throw new LoginException("STARTTLS (explicit TLS) failed");
+			}
+			if (!Util.isEmptyString(username)) {
+				boolean authed = false;
+				try {
+					authed = client.auth(AUTH_METHOD.CRAM_MD5, username, password);
+				} catch (InvalidKeyException | NoSuchAlgorithmException | InvalidKeySpecException e) {
+					e.printStackTrace();
+				}
+				if (!authed && !client.auth(AUTH_METHOD.PLAIN, username, password)) {
+					throw new LoginException("Server rejected AUTH command. Invalid username or password?");
+				}
+			}
+			cleanup = false;
+			this.fromAddress = fromAddress;
+			this.fromName = fromName;
+			this.replyTo = replyTo;
+		} finally {
+			if (cleanup)
+				cleanup();
+		}
+	}
+
+	private void cleanup() {
+		try {
+			client.logout();
+		} catch (Exception e) {
+		}
+		try {
+			client.disconnect();
+		} catch (Exception e) {
+		}
+	}
+
+	private void abort() throws IOException {
+		if (!client.reset())
+			throw new IOException("Cannot abort current mail transaction");
+	}
+
+	public boolean send(String recipient, String subject, String message) {
+		Writer writer;
+		SimpleSMTPHeader header;
+
+		try {
+			header = new QuotingSmtpHeader(fromAddress, fromName, recipient, subject);
+			if (!Util.isEmptyString(replyTo)) {
+				header.addHeaderField("Reply-To", replyTo);
+			}
+			header.addHeaderField("Content-Type", "text/plain; charset=utf-8");
+			header.addHeaderField("Content-Transfer-Encoding", "8bit");
+
+			if (!client.setSender(fromAddress)) {
+				abort();
+				return false;
+			}
+			if (!client.addRecipient(recipient)) {
+				abort();
+				return false;
+			}
+			writer = client.sendMessageData();
+			if (writer == null) {
+				abort();
+				return false;
+			}
+
+			writer.write(header.toString());
+			writer.write(message);
+			writer.close();
+			client.completePendingCommand();
+
+			return true;
+		} catch (IOException e) {
+			cleanup();
+			return false;
+		}
+	}
+
+	public boolean isConnected() {
+		if (!client.isConnected())
+			return false;
+		try {
+			client.sendNoOp();
+			return true;
+		} catch (IOException e) {
+			return false;
+		}
+	}
+
+	public void close() {
+		if (client.isConnected()) {
+			try {
+				client.logout();
+			} catch (Exception e) { // Don't care
+			}
+			try {
+				client.disconnect();
+			} catch (Exception e) { // Don't care
+			}
+		}
+	}
+
+}