renaming eu.siacs.conversations to de.thedevstack.conversationsplus

 "renaming eu.siacs.conversations to de.thedevstack.conversationsplus"

package renaming completed

7 files changed, 1165 insertions, 0 deletions

diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/OtrEngine.java b/src/main/java/de/thedevstack/conversationsplus/crypto/OtrEngine.java
new file mode 100644
index 00000000..dfb64eaf
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/OtrEngine.java
@@ -0,0 +1,303 @@
+package de.thedevstack.conversationsplus.crypto;
+
+import java.math.BigInteger;
+import java.security.KeyFactory;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.NoSuchAlgorithmException;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+import java.security.spec.DSAPrivateKeySpec;
+import java.security.spec.DSAPublicKeySpec;
+import java.security.spec.InvalidKeySpecException;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.util.Log;
+
+import de.thedevstack.conversationsplus.Config;
+import de.thedevstack.conversationsplus.entities.Account;
+import de.thedevstack.conversationsplus.entities.Conversation;
+import de.thedevstack.conversationsplus.services.XmppConnectionService;
+import de.thedevstack.conversationsplus.xmpp.chatstate.ChatState;
+import de.thedevstack.conversationsplus.xmpp.jid.InvalidJidException;
+import de.thedevstack.conversationsplus.xmpp.jid.Jid;
+import de.thedevstack.conversationsplus.xmpp.stanzas.MessagePacket;
+
+import net.java.otr4j.OtrEngineHost;
+import net.java.otr4j.OtrException;
+import net.java.otr4j.OtrPolicy;
+import net.java.otr4j.OtrPolicyImpl;
+import net.java.otr4j.crypto.OtrCryptoEngineImpl;
+import net.java.otr4j.crypto.OtrCryptoException;
+import net.java.otr4j.session.InstanceTag;
+import net.java.otr4j.session.SessionID;
+import net.java.otr4j.session.FragmenterInstructions;
+
+public class OtrEngine extends OtrCryptoEngineImpl implements OtrEngineHost {
+
+	private Account account;
+	private OtrPolicy otrPolicy;
+	private KeyPair keyPair;
+	private XmppConnectionService mXmppConnectionService;
+
+	public OtrEngine(XmppConnectionService service, Account account) {
+		this.account = account;
+		this.otrPolicy = new OtrPolicyImpl();
+		this.otrPolicy.setAllowV1(false);
+		this.otrPolicy.setAllowV2(true);
+		this.otrPolicy.setAllowV3(true);
+		this.keyPair = loadKey(account.getKeys());
+		this.mXmppConnectionService = service;
+	}
+
+	private KeyPair loadKey(JSONObject keys) {
+		if (keys == null) {
+			return null;
+		}
+		try {
+			BigInteger x = new BigInteger(keys.getString("otr_x"), 16);
+			BigInteger y = new BigInteger(keys.getString("otr_y"), 16);
+			BigInteger p = new BigInteger(keys.getString("otr_p"), 16);
+			BigInteger q = new BigInteger(keys.getString("otr_q"), 16);
+			BigInteger g = new BigInteger(keys.getString("otr_g"), 16);
+			KeyFactory keyFactory = KeyFactory.getInstance("DSA");
+			DSAPublicKeySpec pubKeySpec = new DSAPublicKeySpec(y, p, q, g);
+			DSAPrivateKeySpec privateKeySpec = new DSAPrivateKeySpec(x, p, q, g);
+			PublicKey publicKey = keyFactory.generatePublic(pubKeySpec);
+			PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec);
+			return new KeyPair(publicKey, privateKey);
+		} catch (JSONException e) {
+			return null;
+		} catch (NoSuchAlgorithmException e) {
+			return null;
+		} catch (InvalidKeySpecException e) {
+			return null;
+		}
+	}
+
+	private void saveKey() {
+		PublicKey publicKey = keyPair.getPublic();
+		PrivateKey privateKey = keyPair.getPrivate();
+		KeyFactory keyFactory;
+		try {
+			keyFactory = KeyFactory.getInstance("DSA");
+			DSAPrivateKeySpec privateKeySpec = keyFactory.getKeySpec(
+					privateKey, DSAPrivateKeySpec.class);
+			DSAPublicKeySpec publicKeySpec = keyFactory.getKeySpec(publicKey,
+					DSAPublicKeySpec.class);
+			this.account.setKey("otr_x", privateKeySpec.getX().toString(16));
+			this.account.setKey("otr_g", privateKeySpec.getG().toString(16));
+			this.account.setKey("otr_p", privateKeySpec.getP().toString(16));
+			this.account.setKey("otr_q", privateKeySpec.getQ().toString(16));
+			this.account.setKey("otr_y", publicKeySpec.getY().toString(16));
+		} catch (final NoSuchAlgorithmException | InvalidKeySpecException e) {
+			e.printStackTrace();
+		}
+
+    }
+
+	@Override
+	public void askForSecret(SessionID id, InstanceTag instanceTag, String question) {
+		try {
+			final Jid jid = Jid.fromSessionID(id);
+			Conversation conversation = this.mXmppConnectionService.find(this.account,jid);
+			if (conversation!=null) {
+				conversation.smp().hint = question;
+				conversation.smp().status = Conversation.Smp.STATUS_CONTACT_REQUESTED;
+				mXmppConnectionService.updateConversationUi();
+			}
+		} catch (InvalidJidException e) {
+			Log.d(Config.LOGTAG,account.getJid().toBareJid()+": smp in invalid session "+id.toString());
+		}
+	}
+
+	@Override
+	public void finishedSessionMessage(SessionID arg0, String arg1)
+			throws OtrException {
+
+	}
+
+	@Override
+	public String getFallbackMessage(SessionID arg0) {
+		return "I would like to start a private (OTR encrypted) conversation but your client doesn’t seem to support that";
+	}
+
+	@Override
+	public byte[] getLocalFingerprintRaw(SessionID arg0) {
+		try {
+			return getFingerprintRaw(getPublicKey());
+		} catch (OtrCryptoException e) {
+			return null;
+		}
+	}
+
+	public PublicKey getPublicKey() {
+		if (this.keyPair == null) {
+			return null;
+		}
+		return this.keyPair.getPublic();
+	}
+
+	@Override
+	public KeyPair getLocalKeyPair(SessionID arg0) throws OtrException {
+		if (this.keyPair == null) {
+			KeyPairGenerator kg;
+			try {
+				kg = KeyPairGenerator.getInstance("DSA");
+				this.keyPair = kg.genKeyPair();
+				this.saveKey();
+				mXmppConnectionService.databaseBackend.updateAccount(account);
+			} catch (NoSuchAlgorithmException e) {
+				Log.d(Config.LOGTAG,
+						"error generating key pair " + e.getMessage());
+			}
+		}
+		return this.keyPair;
+	}
+
+	@Override
+	public String getReplyForUnreadableMessage(SessionID arg0) {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	public OtrPolicy getSessionPolicy(SessionID arg0) {
+		return otrPolicy;
+	}
+
+	@Override
+	public void injectMessage(SessionID session, String body)
+			throws OtrException {
+		MessagePacket packet = new MessagePacket();
+		packet.setFrom(account.getJid());
+		if (session.getUserID().isEmpty()) {
+			packet.setAttribute("to", session.getAccountID());
+		} else {
+			packet.setAttribute("to", session.getAccountID() + "/" + session.getUserID());
+		}
+		packet.setBody(body);
+		packet.addChild("private", "urn:xmpp:carbons:2");
+		packet.addChild("no-copy", "urn:xmpp:hints");
+		packet.addChild("no-store", "urn:xmpp:hints");
+
+		try {
+			Jid jid = Jid.fromSessionID(session);
+			Conversation conversation = mXmppConnectionService.find(account,jid);
+			if (conversation != null && conversation.setOutgoingChatState(Config.DEFAULT_CHATSTATE)) {
+				if (mXmppConnectionService.sendChatStates()) {
+					packet.addChild(ChatState.toElement(conversation.getOutgoingChatState()));
+				}
+			}
+		} catch (final InvalidJidException ignored) {
+
+		}
+
+		packet.setType(MessagePacket.TYPE_CHAT);
+		account.getXmppConnection().sendMessagePacket(packet);
+	}
+
+	@Override
+	public void messageFromAnotherInstanceReceived(SessionID session) {
+		try {
+			Jid jid = Jid.fromSessionID(session);
+			Conversation conversation = mXmppConnectionService.find(account, jid);
+			String id = conversation == null ? null : conversation.getLastReceivedOtrMessageId();
+			if (id != null) {
+				MessagePacket packet = mXmppConnectionService.getMessageGenerator().generateOtrError(jid,id);
+				packet.setFrom(account.getJid());
+				mXmppConnectionService.sendMessagePacket(account,packet);
+				Log.d(Config.LOGTAG,packet.toString());
+				Log.d(Config.LOGTAG,account.getJid().toBareJid().toString()+": unreadable OTR message in "+conversation.getName());
+			}
+		} catch (InvalidJidException e) {
+			return;
+		}
+	}
+
+	@Override
+	public void multipleInstancesDetected(SessionID arg0) {
+		// TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void requireEncryptedMessage(SessionID arg0, String arg1)
+			throws OtrException {
+		// TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void showError(SessionID arg0, String arg1) throws OtrException {
+		Log.d(Config.LOGTAG,"show error");
+	}
+
+	@Override
+	public void smpAborted(SessionID id) throws OtrException {
+		setSmpStatus(id, Conversation.Smp.STATUS_NONE);
+	}
+
+	private void setSmpStatus(SessionID id, int status) {
+		try {
+			final Jid jid = Jid.fromSessionID(id);
+			Conversation conversation = this.mXmppConnectionService.find(this.account,jid);
+			if (conversation!=null) {
+				conversation.smp().status = status;
+				mXmppConnectionService.updateConversationUi();
+			}
+		} catch (final InvalidJidException ignored) {
+
+		}
+	}
+
+	@Override
+	public void smpError(SessionID id, int arg1, boolean arg2)
+			throws OtrException {
+		setSmpStatus(id, Conversation.Smp.STATUS_NONE);
+	}
+
+	@Override
+	public void unencryptedMessageReceived(SessionID arg0, String arg1)
+			throws OtrException {
+		throw new OtrException(new Exception("unencrypted message received"));
+	}
+
+	@Override
+	public void unreadableMessageReceived(SessionID arg0) throws OtrException {
+		Log.d(Config.LOGTAG,"unreadable message received");
+		throw new OtrException(new Exception("unreadable message received"));
+	}
+
+	@Override
+	public void unverify(SessionID id, String arg1) {
+		setSmpStatus(id, Conversation.Smp.STATUS_FAILED);
+	}
+
+	@Override
+	public void verify(SessionID id, String fingerprint, boolean approved) {
+		Log.d(Config.LOGTAG,"OtrEngine.verify("+id.toString()+","+fingerprint+","+String.valueOf(approved)+")");
+		try {
+			final Jid jid = Jid.fromSessionID(id);
+			Conversation conversation = this.mXmppConnectionService.find(this.account,jid);
+			if (conversation!=null) {
+				if (approved) {
+					conversation.getContact().addOtrFingerprint(fingerprint);
+				}
+				conversation.smp().hint = null;
+				conversation.smp().status = Conversation.Smp.STATUS_VERIFIED;
+				mXmppConnectionService.updateConversationUi();
+				mXmppConnectionService.syncRosterToDisk(conversation.getAccount());
+			}
+		} catch (final InvalidJidException ignored) {
+		}
+	}
+
+	@Override
+	public FragmenterInstructions getFragmenterInstructions(SessionID sessionID) {
+		return null;
+	}
+
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/PgpEngine.java b/src/main/java/de/thedevstack/conversationsplus/crypto/PgpEngine.java
new file mode 100644
index 00000000..b7fa9585
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/PgpEngine.java
@@ -0,0 +1,369 @@
+package de.thedevstack.conversationsplus.crypto;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.URL;
+
+import org.openintents.openpgp.OpenPgpSignatureResult;
+import org.openintents.openpgp.util.OpenPgpApi;
+import org.openintents.openpgp.util.OpenPgpApi.IOpenPgpCallback;
+
+import de.tzur.conversations.Settings;
+import de.thedevstack.conversationsplus.R;
+import de.thedevstack.conversationsplus.entities.Account;
+import de.thedevstack.conversationsplus.entities.Contact;
+import de.thedevstack.conversationsplus.entities.Conversation;
+import de.thedevstack.conversationsplus.entities.DownloadableFile;
+import de.thedevstack.conversationsplus.entities.Message;
+import de.thedevstack.conversationsplus.http.HttpConnectionManager;
+import de.thedevstack.conversationsplus.services.XmppConnectionService;
+import de.thedevstack.conversationsplus.ui.UiCallback;
+import android.app.PendingIntent;
+import android.content.Intent;
+import android.net.Uri;
+
+public class PgpEngine {
+	private OpenPgpApi api;
+	private XmppConnectionService mXmppConnectionService;
+
+	public PgpEngine(OpenPgpApi api, XmppConnectionService service) {
+		this.api = api;
+		this.mXmppConnectionService = service;
+	}
+
+	public void decrypt(final Message message,
+			final UiCallback<Message> callback) {
+		Intent params = new Intent();
+		params.setAction(OpenPgpApi.ACTION_DECRYPT_VERIFY);
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, message
+				.getConversation().getAccount().getJid().toBareJid().toString());
+		if (message.getType() == Message.TYPE_TEXT) {
+			InputStream is = new ByteArrayInputStream(message.getBody()
+					.getBytes());
+			final OutputStream os = new ByteArrayOutputStream();
+			api.executeApiAsync(params, is, os, new IOpenPgpCallback() {
+
+				@Override
+				public void onReturn(Intent result) {
+					switch (result.getIntExtra(OpenPgpApi.RESULT_CODE,
+							OpenPgpApi.RESULT_CODE_ERROR)) {
+					case OpenPgpApi.RESULT_CODE_SUCCESS:
+						try {
+							os.flush();
+							if (message.getEncryption() == Message.ENCRYPTION_PGP) {
+								message.setBody(os.toString());
+								message.setEncryption(Message.ENCRYPTION_DECRYPTED);
+								final HttpConnectionManager manager = mXmppConnectionService.getHttpConnectionManager();
+								if (message.trusted()
+                                        && Settings.DOWNLOAD_IMAGE_LINKS
+                                        && mXmppConnectionService.isDownloadAllowedInConnection()
+										&& message.bodyContainsDownloadable()
+										&& manager.getAutoAcceptFileSize() > 0) {
+									manager.createNewConnection(message);
+								}
+								callback.success(message);
+							}
+						} catch (IOException e) {
+							callback.error(R.string.openpgp_error, message);
+							return;
+						}
+
+						return;
+					case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+						callback.userInputRequried((PendingIntent) result
+								.getParcelableExtra(OpenPgpApi.RESULT_INTENT),
+								message);
+						return;
+					case OpenPgpApi.RESULT_CODE_ERROR:
+						callback.error(R.string.openpgp_error, message);
+                    }
+				}
+			});
+		} else if (message.getType() == Message.TYPE_IMAGE || message.getType() == Message.TYPE_FILE) {
+			try {
+				final DownloadableFile inputFile = this.mXmppConnectionService
+						.getFileBackend().getFile(message, false);
+				final DownloadableFile outputFile = this.mXmppConnectionService
+						.getFileBackend().getFile(message, true);
+				outputFile.getParentFile().mkdirs();
+				outputFile.createNewFile();
+				InputStream is = new FileInputStream(inputFile);
+				OutputStream os = new FileOutputStream(outputFile);
+				api.executeApiAsync(params, is, os, new IOpenPgpCallback() {
+
+					@Override
+					public void onReturn(Intent result) {
+						switch (result.getIntExtra(OpenPgpApi.RESULT_CODE,
+								OpenPgpApi.RESULT_CODE_ERROR)) {
+						case OpenPgpApi.RESULT_CODE_SUCCESS:
+							URL url = message.getImageParams().url;
+							mXmppConnectionService.getFileBackend().updateFileParams(message,url);
+							message.setEncryption(Message.ENCRYPTION_DECRYPTED);
+							PgpEngine.this.mXmppConnectionService
+									.updateMessage(message);
+							inputFile.delete();
+							Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
+							intent.setData(Uri.fromFile(outputFile));
+							mXmppConnectionService.sendBroadcast(intent);
+							callback.success(message);
+							return;
+						case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+							callback.userInputRequried(
+									(PendingIntent) result
+											.getParcelableExtra(OpenPgpApi.RESULT_INTENT),
+									message);
+							return;
+						case OpenPgpApi.RESULT_CODE_ERROR:
+							callback.error(R.string.openpgp_error, message);
+						}
+					}
+				});
+			} catch (final IOException e) {
+				callback.error(R.string.error_decrypting_file, message);
+			}
+
+		}
+	}
+
+	public void encrypt(final Message message,
+			final UiCallback<Message> callback) {
+
+		Intent params = new Intent();
+		params.setAction(OpenPgpApi.ACTION_ENCRYPT);
+		if (message.getConversation().getMode() == Conversation.MODE_SINGLE) {
+			long[] keys = { message.getConversation().getContact()
+					.getPgpKeyId() };
+			params.putExtra(OpenPgpApi.EXTRA_KEY_IDS, keys);
+		} else {
+			params.putExtra(OpenPgpApi.EXTRA_KEY_IDS, message.getConversation()
+					.getMucOptions().getPgpKeyIds());
+		}
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, message
+				.getConversation().getAccount().getJid().toBareJid().toString());
+
+		if (message.getType() == Message.TYPE_TEXT) {
+			params.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+
+			InputStream is = new ByteArrayInputStream(message.getBody()
+					.getBytes());
+			final OutputStream os = new ByteArrayOutputStream();
+			api.executeApiAsync(params, is, os, new IOpenPgpCallback() {
+
+				@Override
+				public void onReturn(Intent result) {
+					switch (result.getIntExtra(OpenPgpApi.RESULT_CODE,
+							OpenPgpApi.RESULT_CODE_ERROR)) {
+					case OpenPgpApi.RESULT_CODE_SUCCESS:
+						try {
+							os.flush();
+							StringBuilder encryptedMessageBody = new StringBuilder();
+							String[] lines = os.toString().split("\n");
+							for (int i = 2; i < lines.length - 1; ++i) {
+								if (!lines[i].contains("Version")) {
+									encryptedMessageBody.append(lines[i]);
+								}
+							}
+							message.setEncryptedBody(encryptedMessageBody
+									.toString());
+							callback.success(message);
+						} catch (IOException e) {
+							callback.error(R.string.openpgp_error, message);
+						}
+
+						break;
+					case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+						callback.userInputRequried((PendingIntent) result
+								.getParcelableExtra(OpenPgpApi.RESULT_INTENT),
+								message);
+						break;
+					case OpenPgpApi.RESULT_CODE_ERROR:
+						callback.error(R.string.openpgp_error, message);
+						break;
+					}
+				}
+			});
+		} else if (message.getType() == Message.TYPE_IMAGE || message.getType() == Message.TYPE_FILE) {
+			try {
+				DownloadableFile inputFile = this.mXmppConnectionService
+						.getFileBackend().getFile(message, true);
+				DownloadableFile outputFile = this.mXmppConnectionService
+						.getFileBackend().getFile(message, false);
+				outputFile.getParentFile().mkdirs();
+				outputFile.createNewFile();
+				InputStream is = new FileInputStream(inputFile);
+				OutputStream os = new FileOutputStream(outputFile);
+				api.executeApiAsync(params, is, os, new IOpenPgpCallback() {
+
+					@Override
+					public void onReturn(Intent result) {
+						switch (result.getIntExtra(OpenPgpApi.RESULT_CODE,
+								OpenPgpApi.RESULT_CODE_ERROR)) {
+						case OpenPgpApi.RESULT_CODE_SUCCESS:
+							callback.success(message);
+							break;
+						case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+							callback.userInputRequried(
+									(PendingIntent) result
+											.getParcelableExtra(OpenPgpApi.RESULT_INTENT),
+									message);
+							break;
+						case OpenPgpApi.RESULT_CODE_ERROR:
+							callback.error(R.string.openpgp_error, message);
+							break;
+						}
+					}
+				});
+			} catch (final IOException e) {
+				callback.error(R.string.openpgp_error, message);
+			}
+		}
+	}
+
+	public long fetchKeyId(Account account, String status, String signature) {
+		if ((signature == null) || (api == null)) {
+			return 0;
+		}
+		if (status == null) {
+			status = "";
+		}
+		final StringBuilder pgpSig = new StringBuilder();
+		pgpSig.append("-----BEGIN PGP SIGNED MESSAGE-----");
+		pgpSig.append('\n');
+		pgpSig.append('\n');
+		pgpSig.append(status);
+		pgpSig.append('\n');
+		pgpSig.append("-----BEGIN PGP SIGNATURE-----");
+		pgpSig.append('\n');
+		pgpSig.append('\n');
+		pgpSig.append(signature.replace("\n", "").trim());
+		pgpSig.append('\n');
+		pgpSig.append("-----END PGP SIGNATURE-----");
+		Intent params = new Intent();
+		params.setAction(OpenPgpApi.ACTION_DECRYPT_VERIFY);
+		params.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, account.getJid().toBareJid().toString());
+		InputStream is = new ByteArrayInputStream(pgpSig.toString().getBytes());
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		Intent result = api.executeApi(params, is, os);
+		switch (result.getIntExtra(OpenPgpApi.RESULT_CODE,
+				OpenPgpApi.RESULT_CODE_ERROR)) {
+		case OpenPgpApi.RESULT_CODE_SUCCESS:
+			OpenPgpSignatureResult sigResult = result
+					.getParcelableExtra(OpenPgpApi.RESULT_SIGNATURE);
+			if (sigResult != null) {
+				return sigResult.getKeyId();
+			} else {
+				return 0;
+			}
+		case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+			return 0;
+		case OpenPgpApi.RESULT_CODE_ERROR:
+			return 0;
+		}
+		return 0;
+	}
+
+	public void generateSignature(final Account account, String status,
+			final UiCallback<Account> callback) {
+		Intent params = new Intent();
+		params.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+		params.setAction(OpenPgpApi.ACTION_SIGN);
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, account.getJid().toBareJid().toString());
+		InputStream is = new ByteArrayInputStream(status.getBytes());
+		final OutputStream os = new ByteArrayOutputStream();
+		api.executeApiAsync(params, is, os, new IOpenPgpCallback() {
+
+			@Override
+			public void onReturn(Intent result) {
+				switch (result.getIntExtra(OpenPgpApi.RESULT_CODE, 0)) {
+				case OpenPgpApi.RESULT_CODE_SUCCESS:
+					StringBuilder signatureBuilder = new StringBuilder();
+					try {
+						os.flush();
+						String[] lines = os.toString().split("\n");
+						boolean sig = false;
+						for (String line : lines) {
+							if (sig) {
+								if (line.contains("END PGP SIGNATURE")) {
+									sig = false;
+								} else {
+									if (!line.contains("Version")) {
+										signatureBuilder.append(line.trim());
+									}
+								}
+							}
+							if (line.contains("BEGIN PGP SIGNATURE")) {
+								sig = true;
+							}
+						}
+					} catch (IOException e) {
+						callback.error(R.string.openpgp_error, account);
+						return;
+					}
+					account.setKey("pgp_signature", signatureBuilder.toString());
+					callback.success(account);
+					return;
+				case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+					callback.userInputRequried((PendingIntent) result
+							.getParcelableExtra(OpenPgpApi.RESULT_INTENT),
+							account);
+					return;
+				case OpenPgpApi.RESULT_CODE_ERROR:
+					callback.error(R.string.openpgp_error, account);
+                }
+			}
+		});
+	}
+
+	public void hasKey(final Contact contact, final UiCallback<Contact> callback) {
+		Intent params = new Intent();
+		params.setAction(OpenPgpApi.ACTION_GET_KEY);
+		params.putExtra(OpenPgpApi.EXTRA_KEY_ID, contact.getPgpKeyId());
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, contact.getAccount()
+				.getJid().toBareJid().toString());
+		api.executeApiAsync(params, null, null, new IOpenPgpCallback() {
+
+			@Override
+			public void onReturn(Intent result) {
+				switch (result.getIntExtra(OpenPgpApi.RESULT_CODE, 0)) {
+				case OpenPgpApi.RESULT_CODE_SUCCESS:
+					callback.success(contact);
+					return;
+				case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+					callback.userInputRequried((PendingIntent) result
+							.getParcelableExtra(OpenPgpApi.RESULT_INTENT),
+							contact);
+					return;
+				case OpenPgpApi.RESULT_CODE_ERROR:
+					callback.error(R.string.openpgp_error, contact);
+                }
+			}
+		});
+	}
+
+	public PendingIntent getIntentForKey(Contact contact) {
+		Intent params = new Intent();
+		params.setAction(OpenPgpApi.ACTION_GET_KEY);
+		params.putExtra(OpenPgpApi.EXTRA_KEY_ID, contact.getPgpKeyId());
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, contact.getAccount()
+				.getJid().toBareJid().toString());
+		Intent result = api.executeApi(params, null, null);
+		return (PendingIntent) result
+				.getParcelableExtra(OpenPgpApi.RESULT_INTENT);
+	}
+
+	public PendingIntent getIntentForKey(Account account, long pgpKeyId) {
+		Intent params = new Intent();
+		params.setAction(OpenPgpApi.ACTION_GET_KEY);
+		params.putExtra(OpenPgpApi.EXTRA_KEY_ID, pgpKeyId);
+		params.putExtra(OpenPgpApi.EXTRA_ACCOUNT_NAME, account.getJid().toBareJid().toString());
+		Intent result = api.executeApi(params, null, null);
+		return (PendingIntent) result
+				.getParcelableExtra(OpenPgpApi.RESULT_INTENT);
+	}
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/DigestMd5.java b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/DigestMd5.java
new file mode 100644
index 00000000..f4c3f28e
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/DigestMd5.java
@@ -0,0 +1,91 @@
+package de.thedevstack.conversationsplus.crypto.sasl;
+
+import android.util.Base64;
+
+import java.math.BigInteger;
+import java.nio.charset.Charset;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+
+import de.thedevstack.conversationsplus.entities.Account;
+import de.thedevstack.conversationsplus.utils.CryptoHelper;
+import de.thedevstack.conversationsplus.xml.TagWriter;
+
+public class DigestMd5 extends SaslMechanism {
+	public DigestMd5(final TagWriter tagWriter, final Account account, final SecureRandom rng) {
+		super(tagWriter, account, rng);
+	}
+
+	@Override
+	public int getPriority() {
+		return 10;
+	}
+
+	@Override
+	public String getMechanism() {
+		return "DIGEST-MD5";
+	}
+
+	private State state = State.INITIAL;
+
+	@Override
+	public String getResponse(final String challenge) throws AuthenticationException {
+		switch (state) {
+			case INITIAL:
+				state = State.RESPONSE_SENT;
+				final String encodedResponse;
+				try {
+					final Tokenizer tokenizer = new Tokenizer(Base64.decode(challenge, Base64.DEFAULT));
+					String nonce = "";
+					for (final String token : tokenizer) {
+						final String[] parts = token.split("=", 2);
+						if (parts[0].equals("nonce")) {
+							nonce = parts[1].replace("\"", "");
+						} else if (parts[0].equals("rspauth")) {
+							return "";
+						}
+					}
+					final String digestUri = "xmpp/" + account.getServer();
+					final String nonceCount = "00000001";
+					final String x = account.getUsername() + ":" + account.getServer() + ":"
+						+ account.getPassword();
+					final MessageDigest md = MessageDigest.getInstance("MD5");
+					final byte[] y = md.digest(x.getBytes(Charset.defaultCharset()));
+					final String cNonce = new BigInteger(100, rng).toString(32);
+					final byte[] a1 = CryptoHelper.concatenateByteArrays(y,
+							(":" + nonce + ":" + cNonce).getBytes(Charset.defaultCharset()));
+					final String a2 = "AUTHENTICATE:" + digestUri;
+					final String ha1 = CryptoHelper.bytesToHex(md.digest(a1));
+					final String ha2 = CryptoHelper.bytesToHex(md.digest(a2.getBytes(Charset
+									.defaultCharset())));
+					final String kd = ha1 + ":" + nonce + ":" + nonceCount + ":" + cNonce
+						+ ":auth:" + ha2;
+					final String response = CryptoHelper.bytesToHex(md.digest(kd.getBytes(Charset
+									.defaultCharset())));
+					final String saslString = "username=\"" + account.getUsername()
+						+ "\",realm=\"" + account.getServer() + "\",nonce=\""
+						+ nonce + "\",cnonce=\"" + cNonce + "\",nc=" + nonceCount
+						+ ",qop=auth,digest-uri=\"" + digestUri + "\",response="
+						+ response + ",charset=utf-8";
+					encodedResponse = Base64.encodeToString(
+							saslString.getBytes(Charset.defaultCharset()),
+							Base64.NO_WRAP);
+				} catch (final NoSuchAlgorithmException e) {
+					throw new AuthenticationException(e);
+				}
+
+				return encodedResponse;
+			case RESPONSE_SENT:
+				state = State.VALID_SERVER_RESPONSE;
+				break;
+			case VALID_SERVER_RESPONSE:
+				if (challenge==null) {
+					return null; //everything is fine
+				}
+			default:
+				throw new InvalidStateException(state);
+		}
+		return null;
+	}
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/Plain.java b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/Plain.java
new file mode 100644
index 00000000..179c12de
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/Plain.java
@@ -0,0 +1,30 @@
+package de.thedevstack.conversationsplus.crypto.sasl;
+
+import android.util.Base64;
+
+import java.nio.charset.Charset;
+
+import de.thedevstack.conversationsplus.entities.Account;
+import de.thedevstack.conversationsplus.xml.TagWriter;
+
+public class Plain extends SaslMechanism {
+	public Plain(final TagWriter tagWriter, final Account account) {
+		super(tagWriter, account, null);
+	}
+
+	@Override
+	public int getPriority() {
+		return 10;
+	}
+
+	@Override
+	public String getMechanism() {
+		return "PLAIN";
+	}
+
+	@Override
+	public String getClientFirstMessage() {
+		final String sasl = '\u0000' + account.getUsername() + '\u0000' + account.getPassword();
+		return Base64.encodeToString(sasl.getBytes(Charset.defaultCharset()), Base64.NO_WRAP);
+	}
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/SaslMechanism.java b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/SaslMechanism.java
new file mode 100644
index 00000000..ed2764c8
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/SaslMechanism.java
@@ -0,0 +1,62 @@
+package de.thedevstack.conversationsplus.crypto.sasl;
+
+import java.security.SecureRandom;
+
+import de.thedevstack.conversationsplus.entities.Account;
+import de.thedevstack.conversationsplus.xml.TagWriter;
+
+public abstract class SaslMechanism {
+
+	final protected TagWriter tagWriter;
+	final protected Account account;
+	final protected SecureRandom rng;
+
+	protected static enum State {
+		INITIAL,
+		AUTH_TEXT_SENT,
+		RESPONSE_SENT,
+		VALID_SERVER_RESPONSE,
+	}
+
+	public static class AuthenticationException extends Exception {
+		public AuthenticationException(final String message) {
+			super(message);
+		}
+
+		public AuthenticationException(final Exception inner) {
+			super(inner);
+		}
+	}
+
+	public static class InvalidStateException extends AuthenticationException {
+		public InvalidStateException(final String message) {
+			super(message);
+		}
+
+		public InvalidStateException(final State state) {
+			this("Invalid state: " + state.toString());
+		}
+	}
+
+	public SaslMechanism(final TagWriter tagWriter, final Account account, final SecureRandom rng) {
+		this.tagWriter = tagWriter;
+		this.account = account;
+		this.rng = rng;
+	}
+
+	/**
+	 * The priority is used to pin the authentication mechanism. If authentication fails, it MAY be retried with another
+	 * mechanism of the same priority, but MUST NOT be tried with a mechanism of lower priority (to prevent downgrade
+	 * attacks).
+	 * @return An arbitrary int representing the priority
+	 */
+	public abstract int getPriority();
+
+	public abstract String getMechanism();
+	public String getClientFirstMessage() {
+		return "";
+	}
+	public String getResponse(final String challenge) throws AuthenticationException {
+		return "";
+	}
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/ScramSha1.java b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/ScramSha1.java
new file mode 100644
index 00000000..af77771c
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/ScramSha1.java
@@ -0,0 +1,232 @@
+package de.thedevstack.conversationsplus.crypto.sasl;
+
+import android.util.Base64;
+import android.util.LruCache;
+
+import org.bouncycastle.crypto.Digest;
+import org.bouncycastle.crypto.digests.SHA1Digest;
+import org.bouncycastle.crypto.macs.HMac;
+import org.bouncycastle.crypto.params.KeyParameter;
+
+import java.math.BigInteger;
+import java.nio.charset.Charset;
+import java.security.InvalidKeyException;
+import java.security.SecureRandom;
+
+import de.thedevstack.conversationsplus.entities.Account;
+import de.thedevstack.conversationsplus.utils.CryptoHelper;
+import de.thedevstack.conversationsplus.xml.TagWriter;
+
+public class ScramSha1 extends SaslMechanism {
+	// TODO: When channel binding (SCRAM-SHA1-PLUS) is supported in future, generalize this to indicate support and/or usage.
+	final private static String GS2_HEADER = "n,,";
+	private String clientFirstMessageBare;
+	private byte[] serverFirstMessage;
+	final private String clientNonce;
+	private byte[] serverSignature = null;
+	private static HMac HMAC;
+	private static Digest DIGEST;
+	private static final byte[] CLIENT_KEY_BYTES = "Client Key".getBytes();
+	private static final byte[] SERVER_KEY_BYTES = "Server Key".getBytes();
+
+	public static class KeyPair {
+		final public byte[] clientKey;
+		final public byte[] serverKey;
+
+		public KeyPair(final byte[] clientKey, final byte[] serverKey) {
+			this.clientKey = clientKey;
+			this.serverKey = serverKey;
+		}
+	}
+
+	private static final LruCache<String, KeyPair> CACHE;
+
+	static {
+		DIGEST = new SHA1Digest();
+		HMAC = new HMac(new SHA1Digest());
+		CACHE = new LruCache<String, KeyPair>(10) {
+			protected KeyPair create(final String k) {
+				// Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations".
+				// Changing any of these values forces a cache miss. `CryptoHelper.bytesToHex()'
+				// is applied to prevent commas in the strings breaking things.
+				final String[] kparts = k.split(",", 4);
+				try {
+					final byte[] saltedPassword, serverKey, clientKey;
+					saltedPassword = hi(CryptoHelper.hexToString(kparts[1]).getBytes(),
+							Base64.decode(CryptoHelper.hexToString(kparts[2]), Base64.DEFAULT), Integer.valueOf(kparts[3]));
+					serverKey = hmac(saltedPassword, SERVER_KEY_BYTES);
+					clientKey = hmac(saltedPassword, CLIENT_KEY_BYTES);
+
+					return new KeyPair(clientKey, serverKey);
+				} catch (final InvalidKeyException | NumberFormatException e) {
+					return null;
+				}
+			}
+		};
+	}
+
+	private State state = State.INITIAL;
+
+	public ScramSha1(final TagWriter tagWriter, final Account account, final SecureRandom rng) {
+		super(tagWriter, account, rng);
+
+		// This nonce should be different for each authentication attempt.
+		clientNonce = new BigInteger(100, this.rng).toString(32);
+		clientFirstMessageBare = "";
+	}
+
+	@Override
+	public int getPriority() {
+		return 20;
+	}
+
+	@Override
+	public String getMechanism() {
+		return "SCRAM-SHA-1";
+	}
+
+	@Override
+	public String getClientFirstMessage() {
+		if (clientFirstMessageBare.isEmpty() && state == State.INITIAL) {
+			clientFirstMessageBare = "n=" + CryptoHelper.saslEscape(CryptoHelper.saslPrep(account.getUsername())) +
+				",r=" + this.clientNonce;
+			state = State.AUTH_TEXT_SENT;
+		}
+		return Base64.encodeToString(
+				(GS2_HEADER + clientFirstMessageBare).getBytes(Charset.defaultCharset()),
+				Base64.NO_WRAP);
+	}
+
+	@Override
+	public String getResponse(final String challenge) throws AuthenticationException {
+		switch (state) {
+			case AUTH_TEXT_SENT:
+				serverFirstMessage = Base64.decode(challenge, Base64.DEFAULT);
+				final Tokenizer tokenizer = new Tokenizer(serverFirstMessage);
+				String nonce = "";
+				int iterationCount = -1;
+				String salt = "";
+				for (final String token : tokenizer) {
+					if (token.charAt(1) == '=') {
+						switch (token.charAt(0)) {
+							case 'i':
+								try {
+									iterationCount = Integer.parseInt(token.substring(2));
+								} catch (final NumberFormatException e) {
+									throw new AuthenticationException(e);
+								}
+								break;
+							case 's':
+								salt = token.substring(2);
+								break;
+							case 'r':
+								nonce = token.substring(2);
+								break;
+							case 'm':
+								/*
+								 * RFC 5802:
+								 * m: This attribute is reserved for future extensibility.  In this
+								 * version of SCRAM, its presence in a client or a server message
+								 * MUST cause authentication failure when the attribute is parsed by
+								 * the other end.
+								 */
+								throw new AuthenticationException("Server sent reserved token: `m'");
+						}
+					}
+				}
+
+				if (iterationCount < 0) {
+					throw new AuthenticationException("Server did not send iteration count");
+				}
+				if (nonce.isEmpty() || !nonce.startsWith(clientNonce)) {
+					throw new AuthenticationException("Server nonce does not contain client nonce: " + nonce);
+				}
+				if (salt.isEmpty()) {
+					throw new AuthenticationException("Server sent empty salt");
+				}
+
+				final String clientFinalMessageWithoutProof = "c=" + Base64.encodeToString(
+						GS2_HEADER.getBytes(), Base64.NO_WRAP) + ",r=" + nonce;
+				final byte[] authMessage = (clientFirstMessageBare + ',' + new String(serverFirstMessage) + ','
+						+ clientFinalMessageWithoutProof).getBytes();
+
+				// Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations".
+				final KeyPair keys = CACHE.get(
+						CryptoHelper.bytesToHex(account.getJid().toBareJid().toString().getBytes()) + ","
+						+ CryptoHelper.bytesToHex(account.getPassword().getBytes()) + ","
+						+ CryptoHelper.bytesToHex(salt.getBytes()) + ","
+						+ String.valueOf(iterationCount)
+						);
+				if (keys == null) {
+					throw new AuthenticationException("Invalid keys generated");
+				}
+				final byte[] clientSignature;
+				try {
+					serverSignature = hmac(keys.serverKey, authMessage);
+					final byte[] storedKey = digest(keys.clientKey);
+
+					clientSignature = hmac(storedKey, authMessage);
+
+				} catch (final InvalidKeyException e) {
+					throw new AuthenticationException(e);
+				}
+
+				final byte[] clientProof = new byte[keys.clientKey.length];
+
+				for (int i = 0; i < clientProof.length; i++) {
+					clientProof[i] = (byte) (keys.clientKey[i] ^ clientSignature[i]);
+				}
+
+
+				final String clientFinalMessage = clientFinalMessageWithoutProof + ",p=" +
+					Base64.encodeToString(clientProof, Base64.NO_WRAP);
+				state = State.RESPONSE_SENT;
+				return Base64.encodeToString(clientFinalMessage.getBytes(), Base64.NO_WRAP);
+			case RESPONSE_SENT:
+				final String clientCalculatedServerFinalMessage = "v=" +
+					Base64.encodeToString(serverSignature, Base64.NO_WRAP);
+				if (!clientCalculatedServerFinalMessage.equals(new String(Base64.decode(challenge, Base64.DEFAULT)))) {
+					throw new AuthenticationException("Server final message does not match calculated final message");
+				}
+				state = State.VALID_SERVER_RESPONSE;
+				return "";
+			default:
+				throw new InvalidStateException(state);
+		}
+	}
+
+	public static synchronized byte[] hmac(final byte[] key, final byte[] input)
+		throws InvalidKeyException {
+		HMAC.init(new KeyParameter(key));
+		HMAC.update(input, 0, input.length);
+		final byte[] out = new byte[HMAC.getMacSize()];
+		HMAC.doFinal(out, 0);
+		return out;
+	}
+
+	public static synchronized byte[] digest(byte[] bytes) {
+		DIGEST.reset();
+		DIGEST.update(bytes, 0, bytes.length);
+		final byte[] out = new byte[DIGEST.getDigestSize()];
+		DIGEST.doFinal(out, 0);
+		return out;
+	}
+
+	/*
+	 * Hi() is, essentially, PBKDF2 [RFC2898] with HMAC() as the
+	 * pseudorandom function (PRF) and with dkLen == output length of
+	 * HMAC() == output length of H().
+	 */
+	private static synchronized byte[] hi(final byte[] key, final byte[] salt, final int iterations)
+		throws InvalidKeyException {
+		byte[] u = hmac(key, CryptoHelper.concatenateByteArrays(salt, CryptoHelper.ONE));
+		byte[] out = u.clone();
+		for (int i = 1; i < iterations; i++) {
+			u = hmac(key, u);
+			for (int j = 0; j < u.length; j++) {
+				out[j] ^= u[j];
+			}
+		}
+		return out;
+	}
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/Tokenizer.java b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/Tokenizer.java
new file mode 100644
index 00000000..cc2805de
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/crypto/sasl/Tokenizer.java
@@ -0,0 +1,78 @@
+package de.thedevstack.conversationsplus.crypto.sasl;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+import java.util.NoSuchElementException;
+
+/**
+ * A tokenizer for GS2 header strings
+ */
+public final class Tokenizer implements Iterator<String>, Iterable<String> {
+	private final List<String> parts;
+	private int index;
+
+	public Tokenizer(final byte[] challenge) {
+		final String challengeString = new String(challenge);
+		parts = new ArrayList<>(Arrays.asList(challengeString.split(",")));
+		// Trim parts.
+		for (int i = 0; i < parts.size(); i++) {
+			parts.set(i, parts.get(i).trim());
+		}
+		index = 0;
+	}
+
+	/**
+	 * Returns true if there is at least one more element, false otherwise.
+	 *
+	 * @see #next
+	 */
+	@Override
+	public boolean hasNext() {
+		return parts.size() != index + 1;
+	}
+
+	/**
+	 * Returns the next object and advances the iterator.
+	 *
+	 * @return the next object.
+	 * @throws java.util.NoSuchElementException if there are no more elements.
+	 * @see #hasNext
+	 */
+	@Override
+	public String next() {
+		if (hasNext()) {
+			return parts.get(index++);
+		} else {
+			throw new NoSuchElementException("No such element. Size is: " + parts.size());
+		}
+	}
+
+	/**
+	 * Removes the last object returned by {@code next} from the collection.
+	 * This method can only be called once between each call to {@code next}.
+	 *
+	 * @throws UnsupportedOperationException if removing is not supported by the collection being
+	 *                                       iterated.
+	 * @throws IllegalStateException         if {@code next} has not been called, or {@code remove} has
+	 *                                       already been called after the last call to {@code next}.
+	 */
+	@Override
+	public void remove() {
+		if(index <= 0) {
+			throw new IllegalStateException("You can't delete an element before first next() method call");
+		}
+		parts.remove(--index);
+	}
+
+	/**
+	 * Returns an {@link java.util.Iterator} for the elements in this object.
+	 *
+	 * @return An {@code Iterator} instance.
+	 */
+	@Override
+	public Iterator<String> iterator() {
+		return parts.iterator();
+	}
+}