Examples with OtrCryptoEngineImpl net.java.otr4j.crypto.OtrCryptoEngineImpl used on opensource projects

Example 6 with OtrCryptoEngineImpl

use of net.java.otr4j.crypto.OtrCryptoEngineImpl in project Conversations by siacs.

the class Account method getOtrFingerprint.

public String getOtrFingerprint() {
    if (this.otrFingerprint == null) {
        try {
            if (this.mOtrService == null) {
                return null;
            }
            final PublicKey publicKey = this.mOtrService.getPublicKey();
            if (publicKey == null || !(publicKey instanceof DSAPublicKey)) {
                return null;
            }
            this.otrFingerprint = new OtrCryptoEngineImpl().getFingerprint(publicKey).toLowerCase(Locale.US);
            return this.otrFingerprint;
        } catch (final OtrCryptoException ignored) {
            return null;
        }
    } else {
        return this.otrFingerprint;
    }
}

Example 7 with OtrCryptoEngineImpl

use of net.java.otr4j.crypto.OtrCryptoEngineImpl in project Zom-Android by zom.

the class SessionImpl method transformSending.

// Retransmit last sent message. Spec document does not mention where or
// when that should happen, must check libotr code.
public String transformSending(String msgText, List<TLV> tlvs) throws OtrException {
    switch(this.getSessionStatus()) {
        case PLAINTEXT:
            if (getSessionPolicy().getRequireEncryption()) {
                lastSentMessage = msgText;
                doTransmitLastMessage = true;
                this.startSession();
                return null;
            } else
                // specification.
                return msgText;
        case ENCRYPTED:
            this.lastSentMessage = msgText;
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, getSessionID().getLocalUserId() + " sends an encrypted message to " + getSessionID().getRemoteUserId() + " through " + getSessionID().getProtocolName() + ".");
            // Get encryption keys.
            SessionKeys encryptionKeys = this.getEncryptionSessionKeys();
            int senderKeyID = encryptionKeys.getLocalKeyID();
            int receipientKeyID = encryptionKeys.getRemoteKeyID();
            // Increment CTR.
            encryptionKeys.incrementSendingCtr();
            byte[] ctr = encryptionKeys.getSendingCtr();
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            if (msgText != null && msgText.length() > 0)
                try {
                    out.write(msgText.getBytes("UTF8"));
                } catch (IOException e) {
                    throw new OtrException(e);
                }
            // Append tlvs
            if (tlvs != null && tlvs.size() > 0) {
                out.write((byte) 0x00);
                OtrOutputStream eoos = new OtrOutputStream(out);
                for (TLV tlv : tlvs) {
                    try {
                        eoos.writeShort(tlv.type);
                        eoos.writeTlvData(tlv.value);
                        eoos.close();
                    } catch (IOException e) {
                        throw new OtrException(e);
                    }
                }
            }
            OtrCryptoEngine otrCryptoEngine = new OtrCryptoEngineImpl();
            byte[] data = out.toByteArray();
            // Encrypt message.
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, "Encrypting message with keyids (localKeyID, remoteKeyID) = (" + senderKeyID + ", " + receipientKeyID + ")");
            byte[] encryptedMsg = otrCryptoEngine.aesEncrypt(encryptionKeys.getSendingAESKey(), ctr, data);
            // Get most recent keys to get the next D-H public key.
            SessionKeys mostRecentKeys = this.getMostRecentSessionKeys();
            DHPublicKey nextDH = (DHPublicKey) mostRecentKeys.getLocalPair().getPublic();
            // Calculate T.
            MysteriousT t = new MysteriousT(2, 0, senderKeyID, receipientKeyID, nextDH, ctr, encryptedMsg);
            // Calculate T hash.
            byte[] sendingMACKey = encryptionKeys.getSendingMACKey();
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, "Transforming T to byte[] to calculate it's HmacSHA1.");
            byte[] serializedT;
            try {
                serializedT = SerializationUtils.toByteArray(t);
            } catch (IOException e) {
                throw new OtrException(e);
            }
            byte[] mac = otrCryptoEngine.sha1Hmac(serializedT, sendingMACKey, SerializationConstants.TYPE_LEN_MAC);
            // Get old MAC keys to be revealed.
            byte[] oldKeys = this.collectOldMacKeys();
            DataMessage m = new DataMessage(t, mac, oldKeys);
            try {
                return SerializationUtils.toString(m);
            } catch (IOException e) {
                throw new OtrException(e);
            }
        case FINISHED:
            this.lastSentMessage = msgText;
            showError("Your message to " + sessionID.getRemoteUserId() + " was not sent.  Either end your private conversation, or restart it.");
            return null;
        default:
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, "Unknown message state, not processing.");
            return msgText;
    }
}

Example 8 with OtrCryptoEngineImpl

use of net.java.otr4j.crypto.OtrCryptoEngineImpl in project Zom-Android by zom.

the class SessionImpl method handleDataMessage.

private synchronized String handleDataMessage(DataMessage data, List<TLV> tlvs) throws OtrException {
    if (DEBUG_ENABLED)
        Log.d(LOG_TAG, getSessionID().getLocalUserId() + " received a data message from " + getSessionID().getRemoteUserId() + ".");
    switch(this.getSessionStatus()) {
        case ENCRYPTED:
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, "Message state is ENCRYPTED. Trying to decrypt message.");
            // Find matching session keys.
            int senderKeyID = data.senderKeyID;
            int receipientKeyID = data.recipientKeyID;
            SessionKeys matchingKeys = this.getSessionKeysByID(receipientKeyID, senderKeyID);
            if (matchingKeys == null) {
                throw new OtrException("no matching keys found");
            }
            // Verify received MAC with a locally calculated MAC.
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, "Transforming T to byte[] to calculate it's HmacSHA1.");
            byte[] serializedT;
            try {
                serializedT = SerializationUtils.toByteArray(data.getT());
            } catch (IOException e) {
                throw new OtrException(e);
            }
            OtrCryptoEngine otrCryptoEngine = new OtrCryptoEngineImpl();
            byte[] computedMAC = otrCryptoEngine.sha1Hmac(serializedT, matchingKeys.getReceivingMACKey(), SerializationConstants.TYPE_LEN_MAC);
            String decryptedMsgContent = null;
            if (!Arrays.equals(computedMAC, data.mac)) {
                // throw new OtrException("MAC verification failed, ignoring message");
                if (DEBUG_ENABLED)
                    Log.d(LOG_TAG, "MAC verification failed, ignoring message");
            } else {
                if (DEBUG_ENABLED)
                    Log.d(LOG_TAG, "Computed HmacSHA1 value matches sent one.");
                // Mark this MAC key as old to be revealed.
                matchingKeys.setIsUsedReceivingMACKey(true);
                matchingKeys.setReceivingCtr(data.ctr);
                byte[] dmc = otrCryptoEngine.aesDecrypt(matchingKeys.getReceivingAESKey(), matchingKeys.getReceivingCtr(), data.encryptedMessage);
                try {
                    // Expect bytes to be text encoded in UTF-8.
                    decryptedMsgContent = new String(dmc, "UTF-8");
                    if (DEBUG_ENABLED)
                        Log.d(LOG_TAG, "Decrypted message: \"" + decryptedMsgContent + "\"");
                    // Handle TLVs
                    if (tlvs == null) {
                        tlvs = new ArrayList<TLV>();
                    }
                    int tlvIndex = decryptedMsgContent.indexOf((char) 0x0);
                    if (tlvIndex > -1) {
                        decryptedMsgContent = decryptedMsgContent.substring(0, tlvIndex);
                        tlvIndex++;
                        byte[] tlvsb = new byte[dmc.length - tlvIndex];
                        System.arraycopy(dmc, tlvIndex, tlvsb, 0, tlvsb.length);
                        ByteArrayInputStream tin = new ByteArrayInputStream(tlvsb);
                        while (tin.available() > 0) {
                            int type;
                            byte[] tdata;
                            OtrInputStream eois = new OtrInputStream(tin);
                            try {
                                type = eois.readShort();
                                tdata = eois.readTlvData();
                                eois.close();
                            } catch (IOException e) {
                                throw new OtrException(e);
                            }
                            tlvs.add(new TLV(type, tdata));
                        }
                    }
                    if (tlvs.size() > 0) {
                        for (TLV tlv : tlvs) {
                            switch(tlv.getType()) {
                                case TLV.DISCONNECTED:
                                    this.setSessionStatus(SessionStatus.FINISHED);
                                    return null;
                                default:
                                    for (OtrTlvHandler handler : tlvHandlers) {
                                        handler.processTlv(tlv);
                                    }
                            }
                        }
                    }
                } catch (UnsupportedEncodingException e) {
                    // throw new OtrException(e);
                    if (DEBUG_ENABLED)
                        Log.e(LOG_TAG, "unsupported encoding exception", e);
                }
            }
            // Rotate keys if necessary.
            SessionKeys mostRecent = this.getMostRecentSessionKeys();
            if (mostRecent.getLocalKeyID() == receipientKeyID)
                this.rotateLocalSessionKeys();
            if (mostRecent.getRemoteKeyID() == senderKeyID)
                this.rotateRemoteSessionKeys(data.nextDH);
            return decryptedMsgContent;
        case FINISHED:
        case PLAINTEXT:
            showError("Unreadable encrypted message was received.");
            refreshSession();
            // "You sent me an unreadable encrypted message"));
            throw new OtrException("Unreadable encrypted message received");
    }
    return null;
}

Example 9 with OtrCryptoEngineImpl

use of net.java.otr4j.crypto.OtrCryptoEngineImpl in project Zom-Android by zom.

the class SessionImpl method rotateLocalSessionKeys.

private void rotateLocalSessionKeys() throws OtrException {
    if (DEBUG_ENABLED)
        Log.d(LOG_TAG, "Rotating local keys.");
    SessionKeys sess1 = getSessionKeysByIndex(SessionKeys.Previous, SessionKeys.Current);
    if (sess1.getIsUsedReceivingMACKey()) {
        if (DEBUG_ENABLED)
            Log.d(LOG_TAG, "Detected used Receiving MAC key. Adding to old MAC keys to reveal it.");
        getOldMacKeys().add(sess1.getReceivingMACKey());
    }
    SessionKeys sess2 = getSessionKeysByIndex(SessionKeys.Previous, SessionKeys.Previous);
    if (sess2.getIsUsedReceivingMACKey()) {
        if (DEBUG_ENABLED)
            Log.d(LOG_TAG, "Detected used Receiving MAC key. Adding to old MAC keys to reveal it.");
        getOldMacKeys().add(sess2.getReceivingMACKey());
    }
    SessionKeys sess3 = getSessionKeysByIndex(SessionKeys.Current, SessionKeys.Current);
    sess1.setLocalPair(sess3.getLocalPair(), sess3.getLocalKeyID());
    SessionKeys sess4 = getSessionKeysByIndex(SessionKeys.Current, SessionKeys.Previous);
    sess2.setLocalPair(sess4.getLocalPair(), sess4.getLocalKeyID());
    KeyPair newPair = new OtrCryptoEngineImpl().generateDHKeyPair();
    sess3.setLocalPair(newPair, sess3.getLocalKeyID() + 1);
    sess4.setLocalPair(newPair, sess4.getLocalKeyID() + 1);
}

Example 10 with OtrCryptoEngineImpl

use of net.java.otr4j.crypto.OtrCryptoEngineImpl in project Zom-Android by zom.

the class SessionImpl method setSessionStatus.

private void setSessionStatus(SessionStatus sessionStatusNew) throws OtrException {
    boolean sessionStatusChanged = (sessionStatus != sessionStatusNew);
    sessionStatus = sessionStatusNew;
    switch(sessionStatus) {
        case ENCRYPTED:
            AuthContext auth = this.getAuthContext(false);
            ess = auth.getS();
            if (DEBUG_ENABLED)
                Log.d(LOG_TAG, "Setting most recent session keys from auth.");
            for (int i = 0; i < this.getSessionKeys()[0].length; i++) {
                SessionKeys current = getSessionKeysByIndex(0, i);
                current.setLocalPair(auth.getLocalDHKeyPair(), 1);
                current.setRemoteDHPublicKey(auth.getRemoteDHPublicKey(), 1);
                current.setS(auth.getS());
            }
            KeyPair nextDH = new OtrCryptoEngineImpl().generateDHKeyPair();
            for (int i = 0; i < this.getSessionKeys()[1].length; i++) {
                SessionKeys current = getSessionKeysByIndex(1, i);
                current.setRemoteDHPublicKey(auth.getRemoteDHPublicKey(), 1);
                current.setLocalPair(nextDH, 2);
            }
            this.setRemotePublicKey(auth.getRemoteLongTermPublicKey());
            auth.reset();
            break;
        case PLAINTEXT:
            // nothing here
            break;
        default:
    }
    if (sessionStatus == SessionStatus.ENCRYPTED && doTransmitLastMessage && lastSentMessage != null) {
        // String retransmit = (isLastMessageRetransmit ? "[resent] " : "");
        String msg = transformSending(lastSentMessage, null);
        getHost().injectMessage(getSessionID(), msg);
        sessionStatusChanged = true;
    }
    doTransmitLastMessage = false;
    isLastMessageRetransmit = false;
    lastSentMessage = null;
    if (sessionStatusChanged) {
        for (OtrEngineListener l : this.listeners) l.sessionStatusChanged(getSessionID());
    }
}