NTCP2: Reduce min downtime for rekeying if hidden

router/java/src/net/i2p/router/transport/ntcp/NTCPTransport.java

@@ -137,6 +137,7 @@ public class NTCPTransport extends TransportImpl {
     private static final int NTCP2_IV_LEN = OutboundNTCP2State.IV_SIZE;
     private static final int NTCP2_KEY_LEN = OutboundNTCP2State.KEY_SIZE;
     private static final long MIN_DOWNTIME_TO_REKEY = 30*24*60*60*1000L;
+    private static final long MIN_DOWNTIME_TO_REKEY_HIDDEN = 24*60*60*1000L;
     private final boolean _enableNTCP1;
     private final boolean _enableNTCP2;
     private final byte[] _ntcp2StaticPubkey;
@@ -252,7 +253,8 @@ public class NTCPTransport extends TransportImpl {
             String b64IV = null;
             String s = null;
             // try to determine if we've been down for 30 days or more
-            boolean shouldRekey = _context.getEstimatedDowntime() >= MIN_DOWNTIME_TO_REKEY;
+            long minDowntime = _context.router().isHidden() ? MIN_DOWNTIME_TO_REKEY_HIDDEN : MIN_DOWNTIME_TO_REKEY;
+            boolean shouldRekey = _context.getEstimatedDowntime() >= minDowntime;
             if (!shouldRekey) {
                 s = ctx.getProperty(PROP_NTCP2_SP);
                 if (s != null) {