/** new style requests need to fill in the tunnel IDs before hand */
private static void prepare(RouterContext ctx, PooledTunnelCreatorConfig cfg) {
int len = cfg.getLength();
boolean isIB = cfg.isInbound();
for (int i = 0; i < len; i++) {
if ((!isIB) && (i == 0)) {
// outbound gateway (us) doesn't receive on a tunnel id
if (len <= 1) { // zero hop, pretend to have a send id
long id = ctx.tunnelDispatcher().getNewOBGWID();
cfg.getConfig(i).setSendTunnelId(DataHelper.toLong(4, id));
}
} else {
long id;
if (isIB && len == 1) id = ctx.tunnelDispatcher().getNewIBZeroHopID();
else if (isIB && i == len - 1) id = ctx.tunnelDispatcher().getNewIBEPID();
else id = 1 + ctx.random().nextLong(TunnelId.MAX_ID_VALUE - 1);
cfg.getConfig(i).setReceiveTunnelId(DataHelper.toLong(4, id));
}
if (i > 0) cfg.getConfig(i - 1).setSendTunnelId(cfg.getConfig(i).getReceiveTunnelId());
byte iv[] = new byte[16];
ctx.random().nextBytes(iv);
cfg.getConfig(i).setReplyIV(iv);
cfg.getConfig(i).setReplyKey(ctx.keyGenerator().generateSessionKey());
}
// This is in BuildExecutor.buildTunnel() now
// And it was overwritten by the one in createTunnelBuildMessage() anyway!
// cfg.setReplyMessageId(ctx.random().nextLong(I2NPMessage.MAX_ID_VALUE));
}
private static void buildZeroHop(
RouterContext ctx, TunnelPool pool, PooledTunnelCreatorConfig cfg, BuildExecutor exec) {
Log log = ctx.logManager().getLog(BuildRequestor.class);
if (log.shouldLog(Log.DEBUG)) log.debug("Build zero hop tunnel " + cfg);
exec.buildComplete(cfg, pool);
if (cfg.isInbound()) ctx.tunnelDispatcher().joinInbound(cfg);
else ctx.tunnelDispatcher().joinOutbound(cfg);
pool.addTunnel(cfg);
exec.buildSuccessful(cfg);
ExpireJob expireJob = new ExpireJob(ctx, cfg, pool);
cfg.setExpireJob(expireJob);
ctx.jobQueue().addJob(expireJob);
// can it get much easier?
}
/**
* If the tunnel is short enough, and everybody in the tunnel, and the OBEP or IBGW for the paired
* tunnel, all support the new variable-sized tunnel build message, then use that, otherwise the
* old 8-entry version.
*
* @return null on error
*/
private static TunnelBuildMessage createTunnelBuildMessage(
RouterContext ctx,
TunnelPool pool,
PooledTunnelCreatorConfig cfg,
TunnelInfo pairedTunnel,
BuildExecutor exec) {
Log log = ctx.logManager().getLog(BuildRequestor.class);
long replyTunnel = 0;
Hash replyRouter = null;
boolean useVariable = SEND_VARIABLE && cfg.getLength() <= MEDIUM_RECORDS;
if (cfg.isInbound()) {
// replyTunnel = 0; // as above
replyRouter = ctx.routerHash();
if (useVariable) {
// check the reply OBEP and all the tunnel peers except ourselves
if (!supportsVariable(ctx, pairedTunnel.getPeer(pairedTunnel.getLength() - 1))) {
useVariable = false;
} else {
for (int i = 0; i < cfg.getLength() - 1; i++) {
if (!supportsVariable(ctx, cfg.getPeer(i))) {
useVariable = false;
break;
}
}
}
}
} else {
replyTunnel = pairedTunnel.getReceiveTunnelId(0).getTunnelId();
replyRouter = pairedTunnel.getPeer(0);
if (useVariable) {
// check the reply IBGW and all the tunnel peers except ourselves
if (!supportsVariable(ctx, replyRouter)) {
useVariable = false;
} else {
for (int i = 1; i < cfg.getLength() - 1; i++) {
if (!supportsVariable(ctx, cfg.getPeer(i))) {
useVariable = false;
break;
}
}
}
}
}
// populate and encrypt the message
TunnelBuildMessage msg;
List<Integer> order;
if (useVariable) {
if (cfg.getLength() <= SHORT_RECORDS) {
msg = new VariableTunnelBuildMessage(ctx, SHORT_RECORDS);
order = new ArrayList<Integer>(SHORT_ORDER);
} else {
msg = new VariableTunnelBuildMessage(ctx, MEDIUM_RECORDS);
order = new ArrayList<Integer>(MEDIUM_ORDER);
}
} else {
msg = new TunnelBuildMessage(ctx);
order = new ArrayList<Integer>(ORDER);
}
// This is in BuildExecutor.buildTunnel() now
// long replyMessageId = ctx.random().nextLong(I2NPMessage.MAX_ID_VALUE);
// cfg.setReplyMessageId(replyMessageId);
Collections.shuffle(order, ctx.random()); // randomized placement within the message
cfg.setReplyOrder(order);
if (log.shouldLog(Log.DEBUG)) log.debug("Build order: " + order + " for " + cfg);
for (int i = 0; i < msg.getRecordCount(); i++) {
int hop = order.get(i).intValue();
PublicKey key = null;
if (BuildMessageGenerator.isBlank(cfg, hop)) {
// erm, blank
} else {
Hash peer = cfg.getPeer(hop);
RouterInfo peerInfo = ctx.netDb().lookupRouterInfoLocally(peer);
if (peerInfo == null) {
if (log.shouldLog(Log.WARN))
log.warn(
"Peer selected for hop "
+ i
+ "/"
+ hop
+ " was not found locally: "
+ peer
+ " for "
+ cfg);
return null;
} else {
key = peerInfo.getIdentity().getPublicKey();
}
}
if (log.shouldLog(Log.DEBUG))
log.debug(cfg.getReplyMessageId() + ": record " + i + "/" + hop + " has key " + key);
BuildMessageGenerator.createRecord(i, hop, msg, cfg, replyRouter, replyTunnel, ctx, key);
}
BuildMessageGenerator.layeredEncrypt(ctx, msg, cfg, order);
return msg;
}
/**
* Send out a build request message.
*
* @param cfg ReplyMessageId must be set
* @return success
*/
public static boolean request(
RouterContext ctx, TunnelPool pool, PooledTunnelCreatorConfig cfg, BuildExecutor exec) {
// new style crypto fills in all the blanks, while the old style waits for replies to fill in
// the next hop, etc
prepare(ctx, cfg);
if (cfg.getLength() <= 1) {
buildZeroHop(ctx, pool, cfg, exec);
return true;
}
Log log = ctx.logManager().getLog(BuildRequestor.class);
cfg.setTunnelPool(pool);
TunnelInfo pairedTunnel = null;
Hash farEnd = cfg.getFarEnd();
TunnelManagerFacade mgr = ctx.tunnelManager();
boolean isInbound = pool.getSettings().isInbound();
if (pool.getSettings().isExploratory() || !usePairedTunnels(ctx)) {
if (isInbound) pairedTunnel = mgr.selectOutboundExploratoryTunnel(farEnd);
else pairedTunnel = mgr.selectInboundExploratoryTunnel(farEnd);
} else {
// building a client tunnel
if (isInbound)
pairedTunnel = mgr.selectOutboundTunnel(pool.getSettings().getDestination(), farEnd);
else pairedTunnel = mgr.selectInboundTunnel(pool.getSettings().getDestination(), farEnd);
if (pairedTunnel == null) {
if (isInbound) {
// random more reliable than closest ??
// pairedTunnel = mgr.selectOutboundExploratoryTunnel(farEnd);
pairedTunnel = mgr.selectOutboundTunnel();
if (pairedTunnel != null
&& pairedTunnel.getLength() <= 1
&& mgr.getOutboundSettings().getLength() > 0
&& mgr.getOutboundSettings().getLength()
+ mgr.getOutboundSettings().getLengthVariance()
> 0) {
// don't build using a zero-hop expl.,
// as it is both very bad for anonomyity,
// and it takes a build slot away from exploratory
pairedTunnel = null;
}
} else {
// random more reliable than closest ??
// pairedTunnel = mgr.selectInboundExploratoryTunnel(farEnd);
pairedTunnel = mgr.selectInboundTunnel();
if (pairedTunnel != null
&& pairedTunnel.getLength() <= 1
&& mgr.getInboundSettings().getLength() > 0
&& mgr.getInboundSettings().getLength() + mgr.getInboundSettings().getLengthVariance()
> 0) {
// ditto
pairedTunnel = null;
}
}
if (pairedTunnel != null && log.shouldLog(Log.INFO))
log.info("Couldn't find a paired tunnel for " + cfg + ", using exploratory tunnel");
}
}
if (pairedTunnel == null) {
if (log.shouldLog(Log.WARN))
log.warn("Tunnel build failed, as we couldn't find a paired tunnel for " + cfg);
exec.buildComplete(cfg, pool);
// Not even an exploratory tunnel? We are in big trouble.
// Let's not spin through here too fast.
// But don't let a client tunnel waiting for exploratories slow things down too much,
// as there may be other tunnel pools who can build
int ms = pool.getSettings().isExploratory() ? 250 : 25;
try {
Thread.sleep(ms);
} catch (InterruptedException ie) {
}
return false;
}
// long beforeCreate = System.currentTimeMillis();
TunnelBuildMessage msg = createTunnelBuildMessage(ctx, pool, cfg, pairedTunnel, exec);
// long createTime = System.currentTimeMillis()-beforeCreate;
if (msg == null) {
if (log.shouldLog(Log.WARN))
log.warn("Tunnel build failed, as we couldn't create the tunnel build message for " + cfg);
exec.buildComplete(cfg, pool);
return false;
}
// cfg.setPairedTunnel(pairedTunnel);
// long beforeDispatch = System.currentTimeMillis();
if (cfg.isInbound()) {
if (log.shouldLog(Log.INFO))
log.info(
"Sending the tunnel build request "
+ msg.getUniqueId()
+ " out the tunnel "
+ pairedTunnel
+ " to "
+ cfg.getPeer(0)
+ " for "
+ cfg
+ " waiting for the reply of "
+ cfg.getReplyMessageId());
// send it out a tunnel targetting the first hop
// TODO - would be nice to have a TunnelBuildFirstHopFailJob queued if the
// pairedTunnel is zero-hop, but no way to do that?
ctx.tunnelDispatcher().dispatchOutbound(msg, pairedTunnel.getSendTunnelId(0), cfg.getPeer(0));
} else {
if (log.shouldLog(Log.INFO))
log.info(
"Sending the tunnel build request directly to "
+ cfg.getPeer(1)
+ " for "
+ cfg
+ " waiting for the reply of "
+ cfg.getReplyMessageId()
+ " with msgId="
+ msg.getUniqueId());
// send it directly to the first hop
// Add some fuzz to the TBM expiration to make it harder to guess how many hops
// or placement in the tunnel
msg.setMessageExpiration(
ctx.clock().now() + BUILD_MSG_TIMEOUT + ctx.random().nextLong(20 * 1000));
// We set the OutNetMessage expiration much shorter, so that the
// TunnelBuildFirstHopFailJob fires before the 13s build expiration.
RouterInfo peer = ctx.netDb().lookupRouterInfoLocally(cfg.getPeer(1));
if (peer == null) {
if (log.shouldLog(Log.WARN))
log.warn("Could not find the next hop to send the outbound request to: " + cfg);
exec.buildComplete(cfg, pool);
return false;
}
OutNetMessage outMsg =
new OutNetMessage(ctx, msg, ctx.clock().now() + FIRST_HOP_TIMEOUT, PRIORITY, peer);
outMsg.setOnFailedSendJob(new TunnelBuildFirstHopFailJob(ctx, pool, cfg, exec));
ctx.outNetMessagePool().add(outMsg);
}
// if (log.shouldLog(Log.DEBUG))
// log.debug("Tunnel build message " + msg.getUniqueId() + " created in " + createTime
// + "ms and dispatched in " + (System.currentTimeMillis()-beforeDispatch));
return true;
}