I2CP: Allow larger client clock skew (ticket #1503),

better error message to client
javadocs

core/java/src/net/i2p/data/i2cp/SessionConfig.java

@@ -41,15 +41,18 @@ public class SessionConfig extends DataStructureImpl {
     private Properties _options;
 
     /** 
-     * if the client authorized this session more than the specified period ago, 
+     * If the client authorized this session more than the specified period ago, 
-     * refuse it, since it may be a replay attack
+     * refuse it, since it may be a replay attack.
      *
+     * Really? See also ClientManager.REQUEST_LEASESET_TIMEOUT.
+     * If I2CP replay attacks are a thing, there's a lot more to do.
      */
-    private final static long OFFSET_VALIDITY = 30 * 1000;
+    private final static long OFFSET_VALIDITY = 3*60*1000;
 
     public SessionConfig() {
         this(null);
     }
+
     public SessionConfig(Destination dest) {
         _destination = dest;
         _creationDate = new Date(Clock.getInstance().now());
@@ -124,6 +127,9 @@ public class SessionConfig extends DataStructureImpl {
     /**
      * Verify that the signature matches the destination's signing public key.
      *
+     * Note that this also returns false if the creation date is too far in the
+     * past or future. See tooOld() and getCreationDate().
+     *
      * @return true only if the signature matches
      */
     public boolean verifySignature() {
@@ -158,6 +164,9 @@ public class SessionConfig extends DataStructureImpl {
         return ok;
     }
 
+    /**
+     *  Misnamed, could be too old or too far in the future.
+     */
     public boolean tooOld() {
         long now = Clock.getInstance().now();
         long earliestValid = now - OFFSET_VALIDITY;

history.txt

@@ -1,4 +1,10 @@
+2015-04-01 zzz
+ * I2CP: Allow larger client clock skew (ticket #1503)
+ * i2psnark: Fix changing data directory on Windows (ticket #1503)
+
 2015-03-31 zzz
+ * API: Fix some client-side APIs to honor defaults in Properties;
+   add javadocs to specify where we do and don't (ticket #1491)
  * i2ptunnel: Fix multiple SSL outproxies in HTTP client
 
 2015-03-29 zzz

router/java/src/net/i2p/router/RouterVersion.java

@@ -18,7 +18,7 @@ public class RouterVersion {
     /** deprecated */
     public final static String ID = "Monotone";
     public final static String VERSION = CoreVersion.VERSION;
-    public final static long BUILD = 14;
+    public final static long BUILD = 15;
 
     /** for example "-test" */
     public final static String EXTRA = "-rc";

router/java/src/net/i2p/router/client/ClientMessageEventListener.java

@@ -12,6 +12,7 @@ import java.util.Properties;
 
 import net.i2p.CoreVersion;
 import net.i2p.crypto.SigType;
+import net.i2p.data.DataHelper;
 import net.i2p.data.Destination;
 import net.i2p.data.Hash;
 import net.i2p.data.Payload;
@@ -213,6 +214,15 @@ class ClientMessageEventListener implements I2CPMessageReader.I2CPMessageEventLi
             if (stype == null || !stype.isAvailable()) {
                 _log.error("Client requested unsupported signature type " + itype);
                 _runner.disconnectClient("Unsupported signature type " + itype);
+            } else if (in.tooOld()) {
+                long skew = _context.clock().now() - in.getCreationDate().getTime();
+                String msg = "Create session message client clock skew? ";
+                if (skew >= 0)
+                    msg += DataHelper.formatDuration(skew) + " in the past";
+                else
+                    msg += DataHelper.formatDuration(0 - skew) + " in the future";
+                _log.error(msg);
+                _runner.disconnectClient(msg);
             } else {
                 _log.error("Signature verification failed on a create session message");
                 _runner.disconnectClient("Invalid signature on CreateSessionMessage");

router/java/src/net/i2p/router/client/LeaseRequestState.java

@@ -29,7 +29,7 @@ class LeaseRequestState {
     private boolean _successful;
 
     /**
-     *  @param expiration absolute time
+     *  @param expiration absolute time, when the request expires (not when the LS expires)
      */
     public LeaseRequestState(Job onGranted, Job onFailed, long expiration, LeaseSet requested) {
         _onGranted = onGranted;