mirror of
https://github.com/vanitasvitae/Smack.git
synced 2024-12-24 03:27:59 +01:00
Business logic for handling read-only devices
This commit is contained in:
parent
afb432dcee
commit
378aa4b262
5 changed files with 123 additions and 83 deletions
|
@ -23,31 +23,56 @@ package org.jivesoftware.smackx.omemo;
|
|||
*/
|
||||
public final class OmemoConfiguration {
|
||||
|
||||
private static boolean IGNORE_READ_ONLY_DEVICES = true;
|
||||
private static int MAX_READ_ONLY_MESSAGE_COUNT = 400;
|
||||
|
||||
/**
|
||||
* Ignore own other stale devices that we did not receive a message from for a period of time.
|
||||
* Ignoring means do not encrypt messages for them. This helps to mitigate stale devices that threaten
|
||||
* forward secrecy by never advancing ratchets.
|
||||
* Set to true, in order to ignore read-only devices.
|
||||
*
|
||||
* @param ignore ignore read-only devices
|
||||
* @see <a href="TODO: Add URL">Blog Post explaining the danger of read-only devices.</a>
|
||||
*/
|
||||
private static boolean IGNORE_STALE_DEVICES = true;
|
||||
private static int IGNORE_STALE_DEVICE_AFTER_HOURS = 24 * 7; //One week
|
||||
|
||||
public static void setIgnoreStaleDevices(boolean ignore) {
|
||||
IGNORE_STALE_DEVICES = ignore;
|
||||
public static void setIgnoreReadOnlyDevices(boolean ignore) {
|
||||
IGNORE_READ_ONLY_DEVICES = ignore;
|
||||
}
|
||||
|
||||
public static boolean getIgnoreStaleDevices() {
|
||||
return IGNORE_STALE_DEVICES;
|
||||
/**
|
||||
* Return true, if the client should stop encrypting messages to a read-only device.
|
||||
*
|
||||
* @return true if read-only devices should get ignored after a certain amount of unanswered messages.
|
||||
* @see <a href="TODO: Add URL">Blog Post explaining the danger of read-only devices.</a>
|
||||
*/
|
||||
public static boolean getIgnoreReadOnlyDevices() {
|
||||
return IGNORE_READ_ONLY_DEVICES;
|
||||
}
|
||||
|
||||
public static void setIgnoreStaleDevicesAfterHours(int hours) {
|
||||
if (hours <= 0) {
|
||||
throw new IllegalArgumentException("Hours must be greater than 0.");
|
||||
/**
|
||||
* Set the maximum amount of messages that the client is allowed to send to a read-only device without getting a
|
||||
* response. Once the message counter of a device reaches that value, the client will stop encrypting messages for
|
||||
* the device (given that {@link #getIgnoreReadOnlyDevices()} is true).
|
||||
* This threshold is used to prevent read-only devices from weakening forward secrecy.
|
||||
*
|
||||
* @param maxReadOnlyMessageCount maximum number of allowed messages to a read-only device.
|
||||
* @see <a href="TODO: Add URL">Blog Post explaining the danger of read-only devices.</a>
|
||||
*/
|
||||
public static void setMaxReadOnlyMessageCount(int maxReadOnlyMessageCount) {
|
||||
if (maxReadOnlyMessageCount <= 0) {
|
||||
throw new IllegalArgumentException("maxReadOnlyMessageCount MUST be greater than 0.");
|
||||
}
|
||||
IGNORE_STALE_DEVICE_AFTER_HOURS = hours;
|
||||
MAX_READ_ONLY_MESSAGE_COUNT = maxReadOnlyMessageCount;
|
||||
}
|
||||
|
||||
public static int getIgnoreStaleDevicesAfterHours() {
|
||||
return IGNORE_STALE_DEVICE_AFTER_HOURS;
|
||||
/**
|
||||
* Get the maximum amount of messages that the client is allowed to send to a read-only device without getting a
|
||||
* response. Once the message counter of a device reaches that value, the client will stop encrypting messages for
|
||||
* the device (given that {@link #getIgnoreReadOnlyDevices()} is true).
|
||||
* This threshold is used to prevent read-only devices from weakening forward secrecy.
|
||||
*
|
||||
* @return maximum number of allowed messages to a read-only device.
|
||||
* @see <a href="TODO: Add URL">Blog Post explaining the danger of read-only devices.</a>
|
||||
*/
|
||||
public static int getMaxReadOnlyMessageCount() {
|
||||
return MAX_READ_ONLY_MESSAGE_COUNT;
|
||||
}
|
||||
|
||||
/**
|
||||
|
|
|
@ -19,6 +19,9 @@ package org.jivesoftware.smackx.omemo;
|
|||
import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.KEYLENGTH;
|
||||
import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.KEYTYPE;
|
||||
|
||||
import javax.crypto.BadPaddingException;
|
||||
import javax.crypto.IllegalBlockSizeException;
|
||||
import javax.crypto.NoSuchPaddingException;
|
||||
import java.io.UnsupportedEncodingException;
|
||||
import java.security.InvalidAlgorithmParameterException;
|
||||
import java.security.InvalidKeyException;
|
||||
|
@ -36,14 +39,10 @@ import java.util.Random;
|
|||
import java.util.Set;
|
||||
import java.util.logging.Level;
|
||||
import java.util.logging.Logger;
|
||||
import javax.crypto.BadPaddingException;
|
||||
import javax.crypto.IllegalBlockSizeException;
|
||||
import javax.crypto.NoSuchPaddingException;
|
||||
|
||||
import org.jivesoftware.smack.SmackException;
|
||||
import org.jivesoftware.smack.XMPPConnection;
|
||||
import org.jivesoftware.smack.XMPPException;
|
||||
|
||||
import org.jivesoftware.smack.packet.Message;
|
||||
import org.jivesoftware.smack.packet.Stanza;
|
||||
import org.jivesoftware.smack.packet.StanzaError;
|
||||
|
@ -62,7 +61,7 @@ import org.jivesoftware.smackx.omemo.exceptions.CorruptedOmemoKeyException;
|
|||
import org.jivesoftware.smackx.omemo.exceptions.CryptoFailedException;
|
||||
import org.jivesoftware.smackx.omemo.exceptions.NoIdentityKeyException;
|
||||
import org.jivesoftware.smackx.omemo.exceptions.NoRawSessionException;
|
||||
import org.jivesoftware.smackx.omemo.exceptions.StaleDeviceException;
|
||||
import org.jivesoftware.smackx.omemo.exceptions.ReadOnlyDeviceException;
|
||||
import org.jivesoftware.smackx.omemo.exceptions.UndecidedOmemoIdentityException;
|
||||
import org.jivesoftware.smackx.omemo.exceptions.UntrustedOmemoIdentityException;
|
||||
import org.jivesoftware.smackx.omemo.internal.CipherAndAuthTag;
|
||||
|
@ -323,6 +322,8 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
|
|||
throw new AssertionError("We MUST have an identityKey for " + contactsDevice + " since we built a session." + e);
|
||||
}
|
||||
|
||||
// Note: We don't need to update our message counter for a ratchet update message.
|
||||
|
||||
return builder.finish();
|
||||
}
|
||||
|
||||
|
@ -386,28 +387,20 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
|
|||
}
|
||||
}
|
||||
|
||||
// Ignore own stale devices
|
||||
if (contactsDevice.getJid().equals(userDevice.getJid()) && OmemoConfiguration.getIgnoreStaleDevices()) {
|
||||
int messageCounter = omemoStore.loadOmemoMessageCounter(userDevice, contactsDevice);
|
||||
|
||||
Date lastMessageDate = getOmemoStoreBackend().getDateOfLastReceivedMessage(userDevice, contactsDevice);
|
||||
if (lastMessageDate == null) {
|
||||
lastMessageDate = new Date();
|
||||
getOmemoStoreBackend().setDateOfLastReceivedMessage(userDevice, contactsDevice, lastMessageDate);
|
||||
}
|
||||
// Ignore read-only devices
|
||||
if (OmemoConfiguration.getIgnoreReadOnlyDevices()) {
|
||||
|
||||
Date lastPublicationDate = getOmemoStoreBackend().getDateOfLastDeviceIdPublication(userDevice, contactsDevice);
|
||||
if (lastPublicationDate == null) {
|
||||
lastPublicationDate = new Date();
|
||||
getOmemoStoreBackend().setDateOfLastDeviceIdPublication(userDevice, contactsDevice, lastPublicationDate);
|
||||
}
|
||||
boolean readOnly = messageCounter >= OmemoConfiguration.getMaxReadOnlyMessageCount();
|
||||
|
||||
boolean stale = isStale(userDevice, contactsDevice, lastPublicationDate, OmemoConfiguration.getIgnoreStaleDevicesAfterHours());
|
||||
stale &= isStale(userDevice, contactsDevice, lastMessageDate, OmemoConfiguration.getIgnoreStaleDevicesAfterHours());
|
||||
if (readOnly) {
|
||||
LOGGER.log(Level.FINE, "Device " + contactsDevice + " seems to be read-only (We sent "
|
||||
+ messageCounter + " messages without getting a reply back (max allowed is " +
|
||||
OmemoConfiguration.getMaxReadOnlyMessageCount() + "). Ignoring the device.");
|
||||
skippedRecipients.put(contactsDevice, new ReadOnlyDeviceException(contactsDevice));
|
||||
|
||||
if (stale) {
|
||||
LOGGER.log(Level.FINE, "Device " + contactsDevice + " seems to be stale (last message received "
|
||||
+ lastMessageDate + ", last publication of deviceId: " + lastPublicationDate + "). Ignore it.");
|
||||
skippedRecipients.put(contactsDevice, new StaleDeviceException(contactsDevice, lastMessageDate, lastPublicationDate));
|
||||
// Skip this device and handle next device
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
@ -428,6 +421,10 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
|
|||
LOGGER.log(Level.WARNING, "Device " + contactsDevice + " is untrusted. Message is not encrypted for it.");
|
||||
skippedRecipients.put(contactsDevice, e);
|
||||
}
|
||||
|
||||
// Increment the message counter of the device
|
||||
omemoStore.storeOmemoMessageCounter(userDevice, contactsDevice,
|
||||
messageCounter + 1);
|
||||
}
|
||||
|
||||
OmemoElement element = builder.finish();
|
||||
|
@ -466,6 +463,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
|
|||
throw new AssertionError("Cannot retrieve OmemoFingerprint of sender although decryption was successful: " + e);
|
||||
}
|
||||
|
||||
// Reset the message counter.
|
||||
omemoStore.storeOmemoMessageCounter(manager.getOwnDevice(), senderDevice, 0);
|
||||
|
||||
if (omemoElement.isMessageElement()) {
|
||||
// Use symmetric message key to decrypt message payload.
|
||||
String plaintext = OmemoRatchet.decryptMessageElement(omemoElement, cipherAndAuthTag);
|
||||
|
@ -1009,24 +1009,6 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
|
|||
return removeStaleDevicesFromDeviceList(userDevice, userDevice.getJid(), deviceList, maxAgeHours);
|
||||
}
|
||||
|
||||
/**
|
||||
* Return a copy of the contactsDeviceList, but with stale devices marked as inactive.
|
||||
* Never mark our own device as stale.
|
||||
* This method ignores {@link OmemoConfiguration#getIgnoreStaleDevices()}!
|
||||
*
|
||||
* In this case, a stale device is one of our devices, from which we haven't received an OMEMO message from
|
||||
* for more than {@link OmemoConfiguration#IGNORE_STALE_DEVICE_AFTER_HOURS} hours.
|
||||
*
|
||||
* @param userDevice our OmemoDevice
|
||||
* @param contact subjects BareJid
|
||||
* @param contactsDeviceList subjects deviceList
|
||||
* @return
|
||||
*/
|
||||
private OmemoCachedDeviceList ignoreStaleDevices(OmemoDevice userDevice, BareJid contact, OmemoCachedDeviceList contactsDeviceList) {
|
||||
int maxAgeHours = OmemoConfiguration.getIgnoreStaleDevicesAfterHours();
|
||||
return removeStaleDevicesFromDeviceList(userDevice, contact, contactsDeviceList, maxAgeHours);
|
||||
}
|
||||
|
||||
/**
|
||||
* Return a copy of the given deviceList of user contact, but with stale devices marked as inactive.
|
||||
* Never mark our own device as stale. If we haven't yet received a message from a device, store the current date
|
||||
|
@ -1086,12 +1068,14 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
|
|||
}
|
||||
|
||||
/**
|
||||
* Determine, whether another one of *our* devices is stale or not.
|
||||
*
|
||||
* @param userDevice
|
||||
* @param subject
|
||||
* @param lastReceipt
|
||||
* @param maxAgeHours
|
||||
* @return
|
||||
* @param userDevice our omemoDevice
|
||||
* @param subject another one of our devices
|
||||
* @param lastReceipt date of last received message from that device
|
||||
* @param maxAgeHours threshold
|
||||
*
|
||||
* @return staleness
|
||||
*/
|
||||
static boolean isStale(OmemoDevice userDevice, OmemoDevice subject, Date lastReceipt, int maxAgeHours) {
|
||||
if (userDevice.equals(subject)) {
|
||||
|
|
|
@ -0,0 +1,52 @@
|
|||
/**
|
||||
*
|
||||
* Copyright 2018 Paul Schaub
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
package org.jivesoftware.smackx.omemo.exceptions;
|
||||
|
||||
import org.jivesoftware.smackx.omemo.OmemoConfiguration;
|
||||
import org.jivesoftware.smackx.omemo.internal.OmemoDevice;
|
||||
|
||||
/**
|
||||
* Exception that signals, that a device is considered read-only.
|
||||
* Read-only devices are devices that receive OMEMO messages, but do not send any.
|
||||
* Those devices are weakening forward secrecy. For that reason, read-only devices are ignored after n messages have
|
||||
* been sent without getting a reply back.
|
||||
*/
|
||||
public class ReadOnlyDeviceException extends Exception {
|
||||
private static final long serialVersionUID = 1L;
|
||||
|
||||
private final OmemoDevice device;
|
||||
|
||||
/**
|
||||
* Constructor.
|
||||
* We do not need to hand over the current value of the message counter, as that value will always be equal to
|
||||
* {@link OmemoConfiguration#getMaxReadOnlyMessageCount()}. Therefore providing the {@link OmemoDevice} should be
|
||||
* enough.
|
||||
*
|
||||
* @param device device which is considered read-only.
|
||||
*/
|
||||
public ReadOnlyDeviceException(OmemoDevice device) {
|
||||
this.device = device;
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the device in question.
|
||||
* @return device
|
||||
*/
|
||||
public OmemoDevice getDevice() {
|
||||
return device;
|
||||
}
|
||||
}
|
|
@ -52,20 +52,6 @@ public class OmemoConfigurationTest {
|
|||
// Expected.
|
||||
}
|
||||
|
||||
// Ignore stale device
|
||||
OmemoConfiguration.setIgnoreStaleDevices(false);
|
||||
assertEquals(false, OmemoConfiguration.getIgnoreStaleDevices());
|
||||
OmemoConfiguration.setIgnoreStaleDevices(true);
|
||||
assertEquals(true, OmemoConfiguration.getIgnoreStaleDevices());
|
||||
OmemoConfiguration.setIgnoreStaleDevicesAfterHours(44);
|
||||
assertEquals(44, OmemoConfiguration.getIgnoreStaleDevicesAfterHours());
|
||||
try {
|
||||
OmemoConfiguration.setIgnoreStaleDevicesAfterHours(-5);
|
||||
TestCase.fail("OmemoConfiguration.setIgnoreStaleDevicesAfterHours should not accept values <= 0.");
|
||||
} catch (IllegalArgumentException e) {
|
||||
// Expected
|
||||
}
|
||||
|
||||
// Renew signedPreKeys
|
||||
OmemoConfiguration.setRenewOldSignedPreKeys(false);
|
||||
assertEquals(false, OmemoConfiguration.getRenewOldSignedPreKeys());
|
||||
|
|
|
@ -32,7 +32,6 @@ import org.jxmpp.stringprep.XmppStringprepException;
|
|||
public class OmemoServiceTest extends SmackTestSuite {
|
||||
|
||||
private static final long ONE_HOUR = 1000L * 60 * 60;
|
||||
private static final int IGNORE_STALE = OmemoConfiguration.getIgnoreStaleDevicesAfterHours();
|
||||
private static final int DELETE_STALE = OmemoConfiguration.getDeleteStaleDevicesAfterHours();
|
||||
|
||||
@Test(expected = IllegalStateException.class)
|
||||
|
@ -55,15 +54,9 @@ public class OmemoServiceTest extends SmackTestSuite {
|
|||
OmemoDevice other = new OmemoDevice(JidCreate.bareFrom("bob@builder.tv"), 444);
|
||||
|
||||
Date now = new Date();
|
||||
Date ignoreMe = new Date(now.getTime() - ((IGNORE_STALE + 1) * ONE_HOUR));
|
||||
Date deleteMe = new Date(now.getTime() - ((DELETE_STALE + 1) * ONE_HOUR));
|
||||
Date imFine = new Date(now.getTime() - ONE_HOUR);
|
||||
|
||||
// One hour "old" devices are (probably) not not stale
|
||||
assertFalse(OmemoService.isStale(user, other, imFine, IGNORE_STALE));
|
||||
|
||||
// Devices one hour "older" than max ages are stale
|
||||
assertTrue(OmemoService.isStale(user, other, ignoreMe, IGNORE_STALE));
|
||||
assertTrue(OmemoService.isStale(user, other, deleteMe, DELETE_STALE));
|
||||
|
||||
// Own device is never stale, no matter how old
|
||||
|
|
Loading…
Reference in a new issue