/**
* Computes and returns the hash of the specified <tt>capsString</tt> using the specified
* <tt>hashAlgorithm</tt>.
*
* @param hashAlgorithm the name of the algorithm to be used to generate the hash
* @param capsString the capabilities string that we'd like to compute a hash for.
* @return the hash of <tt>capsString</tt> computed by the specified <tt>hashAlgorithm</tt> or
* <tt>null</tt> if generating the hash has failed
*/
private static String capsToHash(String hashAlgorithm, String capsString) {
try {
MessageDigest md = MessageDigest.getInstance(hashAlgorithm);
byte[] digest = md.digest(capsString.getBytes());
return Base64.encodeBytes(digest);
} catch (NoSuchAlgorithmException nsae) {
logger.error("Unsupported XEP-0115: Entity Capabilities hash algorithm: " + hashAlgorithm);
return null;
}
}
/**
* Sends enable or disable carbon packet to the server.
*
* @param enable if <tt>true</tt> sends enable packet otherwise sends disable packet.
*/
private void enableDisableCarbon(final boolean enable) {
IQ iq =
new IQ() {
@Override
public String getChildElementXML() {
return "<" + (enable ? "enable" : "disable") + " xmlns='urn:xmpp:carbons:2' />";
}
};
Packet response = null;
try {
PacketCollector packetCollector =
jabberProvider
.getConnection()
.createPacketCollector(new PacketIDFilter(iq.getPacketID()));
iq.setFrom(jabberProvider.getOurJID());
iq.setType(IQ.Type.SET);
jabberProvider.getConnection().sendPacket(iq);
response = packetCollector.nextResult(SmackConfiguration.getPacketReplyTimeout());
packetCollector.cancel();
} catch (Exception e) {
logger.error("Failed to enable carbon.", e);
}
isCarbonEnabled = false;
if (response == null) {
logger.error("Failed to enable carbon. No response is received.");
} else if (response.getError() != null) {
logger.error("Failed to enable carbon: " + response.getError());
} else if (!(response instanceof IQ) || !((IQ) response).getType().equals(IQ.Type.RESULT)) {
logger.error("Failed to enable carbon. The response is not correct.");
} else {
isCarbonEnabled = true;
}
}
/**
* Retrieve DiscoverInfo for a specific node.
*
* @param caps the <tt>Caps</tt> i.e. the node, the hash and the ver
* @return The corresponding DiscoverInfo or null if none is known.
*/
public static DiscoverInfo getDiscoverInfoByCaps(Caps caps) {
synchronized (caps2discoverInfo) {
DiscoverInfo discoverInfo = caps2discoverInfo.get(caps);
/*
* If we don't have the discoverInfo in the runtime cache yet, we
* may have it remembered in a previous application instance.
*/
if (discoverInfo == null) {
ConfigurationService configurationService = getConfigService();
String capsPropertyName = getCapsPropertyName(caps);
String xml = configurationService.getString(capsPropertyName);
if ((xml != null) && (xml.length() != 0)) {
IQProvider discoverInfoProvider =
(IQProvider)
ProviderManager.getInstance()
.getIQProvider("query", "http://jabber.org/protocol/disco#info");
if (discoverInfoProvider != null) {
XmlPullParser parser = new MXParser();
try {
parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, true);
parser.setInput(new StringReader(xml));
// Start the parser.
parser.next();
} catch (XmlPullParserException xppex) {
parser = null;
} catch (IOException ioex) {
parser = null;
}
if (parser != null) {
try {
discoverInfo = (DiscoverInfo) discoverInfoProvider.parseIQ(parser);
} catch (Exception ex) {
}
if (discoverInfo != null) {
if (caps.isValid(discoverInfo)) caps2discoverInfo.put(caps, discoverInfo);
else {
logger.error(
"Invalid DiscoverInfo for " + caps.getNodeVer() + ": " + discoverInfo);
/*
* The discoverInfo doesn't seem valid
* according to the caps which means that we
* must have stored invalid information.
* Delete the invalid information in order
* to not try to validate it again.
*/
configurationService.removeProperty(capsPropertyName);
}
}
}
}
}
}
return discoverInfo;
}
}
