* SendMessageOptions: Increase tag fields to 4 bits and use

table lookup for more flexibility
 * Streaming: Use packet type and current window size to adjust
              number of tags sent and tag threshold, to improve
              efficiency and reliability

apps/streaming/java/src/net/i2p/client/streaming/PacketQueue.java

@@ -3,6 +3,7 @@ package net.i2p.client.streaming;
 import net.i2p.I2PAppContext;
 import net.i2p.client.I2PSession;
 import net.i2p.client.I2PSessionException;
+import net.i2p.client.SendMessageOptions;
 import net.i2p.data.ByteArray;
 import net.i2p.util.ByteCache;
 import net.i2p.util.Log;
@@ -22,6 +23,16 @@ class PacketQueue {
     private final ConnectionManager _connectionManager;
     private final ByteCache _cache = ByteCache.getInstance(64, 36*1024);
     
+    private static final int FLAGS_INITIAL_TAGS = Packet.FLAG_SYNCHRONIZE;
+    private static final int FLAGS_FINAL_TAGS = Packet.FLAG_CLOSE |
+                                              Packet.FLAG_RESET |
+                                              Packet.FLAG_ECHO;
+    private static final int INITIAL_TAGS_TO_SEND = 32;
+    private static final int MIN_TAG_THRESHOLD = 20;
+    private static final int TAG_WINDOW_FACTOR = 5;
+    private static final int FINAL_TAGS_TO_SEND = 4;
+    private static final int FINAL_TAG_THRESHOLD = 2;
+
     public PacketQueue(I2PAppContext context, I2PSession session, ConnectionManager mgr) {
         _context = context;
         _session = session;
@@ -88,24 +99,34 @@ class PacketQueue {
                 // we want the router to expire it a little before we do,
                 // so if we retransmit it will use a new tunnel/lease combo
                 expires = rpe.getNextSendTime() - 500;
+            SendMessageOptions options = new SendMessageOptions();
             if (expires > 0)
-                // I2PSessionImpl2
+                options.setDate(expires);
-                //sent = _session.sendMessage(packet.getTo(), buf, 0, size, keyUsed, tagsSent, expires);
+            if (packet.isFlagSet(FLAGS_INITIAL_TAGS)) {
-                // I2PSessionMuxedImpl
+                Connection con = packet.getConnection();
-                //sent = _session.sendMessage(packet.getTo(), buf, 0, size, keyUsed, tagsSent, expires,
+                if (con != null && con.isInbound())
-                //                 I2PSession.PROTO_STREAMING, I2PSession.PORT_UNSPECIFIED, I2PSession.PORT_UNSPECIFIED);
+                    options.setSendLeaseSet(false);
-                // I2PSessionMuxedImpl no tags
+                options.setTagsToSend(INITIAL_TAGS_TO_SEND);
-                sent = _session.sendMessage(packet.getTo(), buf, 0, size, null, null, expires,
+                options.setTagThreshold(MIN_TAG_THRESHOLD);
-                                 I2PSession.PROTO_STREAMING, packet.getLocalPort(), packet.getRemotePort());
+            } else if (packet.isFlagSet(FLAGS_FINAL_TAGS)) {
-            else
+                options.setSendLeaseSet(false);
-                // I2PSessionImpl2
+                options.setTagsToSend(FINAL_TAGS_TO_SEND);
-                //sent = _session.sendMessage(packet.getTo(), buf, 0, size, keyUsed, tagsSent, 0);
+                options.setTagThreshold(FINAL_TAG_THRESHOLD);
-                // I2PSessionMuxedImpl
+            } else {
-                //sent = _session.sendMessage(packet.getTo(), buf, 0, size, keyUsed, tagsSent,
+                Connection con = packet.getConnection();
-                //                 I2PSession.PROTO_STREAMING, I2PSession.PORT_UNSPECIFIED, I2PSession.PORT_UNSPECIFIED);
+                if (con != null) {
-                // I2PSessionMuxedImpl no tags
+                    if (con.isInbound() && con.getLifetime() < 2*60*1000)
-                sent = _session.sendMessage(packet.getTo(), buf, 0, size, null, null,
+                        options.setSendLeaseSet(false);
-                                 I2PSession.PROTO_STREAMING, packet.getLocalPort(), packet.getRemotePort());
+                    // increase threshold with higher window sizes to prevent stalls
+                    // after tag delivery failure
+                    int wdw = con.getOptions().getWindowSize();
+                    int thresh = Math.max(MIN_TAG_THRESHOLD, wdw * TAG_WINDOW_FACTOR);
+                    options.setTagThreshold(thresh);
+                }
+            }
+            sent = _session.sendMessage(packet.getTo(), buf, 0, size,
+                                 I2PSession.PROTO_STREAMING, packet.getLocalPort(), packet.getRemotePort(),
+                                 options);
             end = _context.clock().now();
             
             if ( (end-begin > 1000) && (_log.shouldLog(Log.WARN)) ) 

core/java/src/net/i2p/client/SendMessageOptions.java

@@ -21,39 +21,32 @@ public class SendMessageOptions extends DateAndFlags {
     /**
      *  1 means don't send, 0 means default
      */
-    private static final int LS_MASK = 0x0001;
+    private static final int LS_MASK = 0x0100;
 
     /**
      *  Tags to send field:
-     *<pre>
+     *  see below for possible values
-     *  000 - default
-     *  001 -   2
-     *  010 -   4
-     *  011 -   8
-     *  100 -  16
-     *  101 -  32
-     *  110 -  64
-     *  111 - 128
-     *</pre>
      */
-    private static final int TAGS_SEND_MASK = 0x000e;
+    private static final int TAGS_SEND_MASK = 0x000f;
-    private static final int MAX_SEND_TAGS = 128;
+    /**
+     *  Possible values. Configured values will be rounded down.
+     *  Note that ElGamalAESEngine enforces a max of 200 on receive.
+     */
+    private static final int[] TAGS_SEND = {
+                                             0, 2, 4, 6, 8, 12, 16, 24,
+                                             32, 40, 51, 64, 80, 100, 125, 160
+                                           };
 
     /**
      *  Tags threshold field:
-     *<pre>
+     *  see below for possible values
-     *  000 - default
-     *  001 -  1
-     *  010 -  2
-     *  011 -  4
-     *  100 -  8
-     *  101 - 16
-     *  110 - 32
-     *  111 - 64
-     *</pre>
      */
-    private static final int TAGS_REQD_MASK = 0x0070;
+    private static final int TAGS_REQD_MASK = 0x00f0;
-    private static final int MAX_REQD_TAGS = 64;
+    /** Possible values. Configured values will be rounded down. */
+    private static final int[] TAGS_REQD = {
+                                             0, 2, 3, 6, 9, 14, 20, 27,
+                                             35, 45, 57, 72, 92, 117, 147, 192
+                                           };
 
     /** default true */
     public void setSendLeaseSet(boolean yes) {
@@ -76,19 +69,19 @@ public class SendMessageOptions extends DateAndFlags {
     /**
      *  If we are low on tags, send this many.
      *  Power of 2 recommended - rounds down.
-     *  default 0, meaning unset
+     *  default 0, meaning unset, use the SKM config (default 40)
      *  @param tags 0 or 2 to 128
      */
     public void setTagsToSend(int tags) {
         if (tags < 0)
             throw new IllegalArgumentException();
         _flags &= ~TAGS_SEND_MASK;
-        _flags |= linToExp(Math.min(tags, MAX_SEND_TAGS) / 2) << 1;
+        _flags |= valToCode(tags, TAGS_SEND);
     }
 
     /**
      *  If we are low on tags, send this many.
-     *  @return default 0, meaning unset
+     *  @return default 0, meaning unset, use the SKM config (default 40)
      */
     public int getTagsToSend() {
         return getTagsToSend(_flags);
@@ -96,29 +89,29 @@ public class SendMessageOptions extends DateAndFlags {
 
     /**
      *  If we are low on tags, send this many.
-     *  @return default 0, meaning unset
+     *  @return default 0, meaning unset, use the SKM config (default 40)
      */
     public static int getTagsToSend(int flags) {
-        int exp = (flags & TAGS_SEND_MASK) >> 1;
+        int exp = (flags & TAGS_SEND_MASK);
-        return 2 * expToLin(exp);
+        return codeToVal(exp, TAGS_SEND);
     }
 
     /**
      *  Low tag threshold. If less than this many, send more.
      *  Power of 2 recommended - rounds down.
-     *  default 0, meaning unset
+     *  default 0, meaning unset, use the SKM config (default 30)
-     *  @param tags 0 to 64
+     *  @param tags 0 to 90
      */
     public void setTagThreshold(int tags) {
         if (tags < 0)
             throw new IllegalArgumentException();
         _flags &= ~TAGS_REQD_MASK;
-        _flags |= linToExp(Math.min(tags, MAX_REQD_TAGS)) << 4;
+        _flags |= valToCode(tags, TAGS_REQD) << 4;
     }
 
     /**
      *  Low tag threshold. If less than this many, send more.
-     *  @return default 0, meaning unset
+     *  @return default 0, meaning unset, use the SKM config (default 30)
      */
     public int getTagThreshold() {
         return getTagThreshold(_flags);
@@ -126,26 +119,26 @@ public class SendMessageOptions extends DateAndFlags {
 
     /**
      *  Low tag threshold. If less than this many, send more.
-     *  @return default 0, meaning unset
+     *  @return default 0, meaning unset, use the SKM config (default 30)
      */
     public static int getTagThreshold(int flags) {
         int exp = (flags & TAGS_REQD_MASK) >> 4;
-        return expToLin(exp);
+        return codeToVal(exp, TAGS_REQD);
     }
 
     /** rounds down */
-    private static int linToExp(int lin) {
+    private static int valToCode(int val, int[] codes) {
-        int exp = 0;
+        // special case, round up so we don't turn it into default
-        while (lin > 0) {
+        if (val > 0 && val <= codes[1])
-            exp++;
+            return 1;
-            lin >>= 1;
+        for (int i = 1; i < codes.length; i++) {
+            if (val < codes[i])
+                return i - 1;
         }
-        return exp;
+        return codes.length - 1;
     }
 
-    private static int expToLin(int exp) {
+    private static int codeToVal(int code, int[] codes) {
-        if (exp <= 0)
+        return codes[code];
-            return 0;
-        return 1 << (exp - 1);
     }
 }

core/java/src/net/i2p/crypto/ElGamalAESEngine.java

@@ -38,6 +38,8 @@ public class ElGamalAESEngine {
     private final Log _log;
     private final static int MIN_ENCRYPTED_SIZE = 80; // smallest possible resulting size
     private final I2PAppContext _context;
+    /** enforced since release 0.6 */
+    public static final int MAX_TAGS_RECEIVED = 200;
 
     public ElGamalAESEngine(I2PAppContext ctx) {
         _context = ctx;
@@ -328,7 +330,7 @@ public class ElGamalAESEngine {
             //ByteArrayInputStream bais = new ByteArrayInputStream(decrypted);
             int cur = 0;
             long numTags = DataHelper.fromLong(decrypted, cur, 2);
-            if ((numTags < 0) || (numTags > 200)) throw new Exception("Invalid number of session tags");
+            if ((numTags < 0) || (numTags > MAX_TAGS_RECEIVED)) throw new Exception("Invalid number of session tags");
             if (numTags > 0) tags = new ArrayList((int)numTags);
             cur += 2;
             //_log.debug("# tags: " + numTags);

history.txt

@@ -1,3 +1,12 @@
+2012-08-26 zzz
+ * DataHelper: Trim trailing whitespace when loading properties
+ * NetDB: Increase floodfills, decrease flood redundancy
+ * SendMessageOptions: Increase tag fields to 4 bits and use
+                       table lookup for more flexibility
+ * Streaming: Use packet type and current window size to adjust
+              number of tags sent and tag threshold, to improve
+              efficiency and reliability
+
 2012-08-25 kytv
  * Dutch and German translation updates from Transifex
  * Router console typo fixes (#701)

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 = 18;
+    public final static long BUILD = 19;
 
     /** for example "-test" */
     public final static String EXTRA = "";