Ratchet: Remove ID and DI from ACKREQ block

Use callback != null to specify request for ack

router/java/src/net/i2p/router/crypto/ratchet/ECIESAEADEngine.java

@@ -26,7 +26,6 @@ import net.i2p.data.PrivateKey;
 import net.i2p.data.PublicKey;
 import net.i2p.data.SessionKey;
 import net.i2p.data.SessionTag;
-import net.i2p.data.i2np.DeliveryInstructions;
 import net.i2p.data.i2np.GarlicClove;
 import static net.i2p.router.crypto.ratchet.RatchetPayload.*;
 import net.i2p.router.RouterContext;
@@ -563,16 +562,15 @@ public final class ECIESAEADEngine {
      *
      * @param target public key to which the data should be encrypted. 
      * @param priv local private key to encrypt with, from the leaseset
-     * @param replyDI non-null to request an ack, or null
-     * @param callback may be null
+     * @param callback may be null, if non-null an ack will be requested (except NS/NSR)
      * @return encrypted data or null on failure
      *
      */
     public byte[] encrypt(CloveSet cloves, PublicKey target, PrivateKey priv,
-                          RatchetSKM keyManager, DeliveryInstructions replyDI,
+                          RatchetSKM keyManager,
                           ReplyCallback callback) {
         try {
-            return x_encrypt(cloves, target, priv, keyManager, replyDI, callback);
+            return x_encrypt(cloves, target, priv, keyManager, callback);
         } catch (Exception e) {
             _log.error("ECIES encrypt error", e);
             return null;
@@ -580,7 +578,7 @@ public final class ECIESAEADEngine {
     }
 
     private byte[] x_encrypt(CloveSet cloves, PublicKey target, PrivateKey priv,
-                             RatchetSKM keyManager, DeliveryInstructions replyDI,
+                             RatchetSKM keyManager,
                              ReplyCallback callback) {
         if (target.getType() != EncType.ECIES_X25519)
             throw new IllegalArgumentException();
@@ -594,8 +592,7 @@ public final class ECIESAEADEngine {
         if (re == null) {
             if (_log.shouldDebug())
                 _log.debug("Encrypting as NS to " + target);
-            // no ack in NS
-            return encryptNewSession(cloves, target, priv, keyManager, null, callback);
+            return encryptNewSession(cloves, target, priv, keyManager, callback);
         }
 
         HandshakeState state = re.key.getHandshakeState();
@@ -609,12 +606,11 @@ public final class ECIESAEADEngine {
             }
             if (_log.shouldDebug())
                 _log.debug("Encrypting as NSR to " + target + " with tag " + re.tag.toBase64());
-            // no ack in NSR
-            return encryptNewSessionReply(cloves, target, state, re.tag, keyManager, null, callback);
+            return encryptNewSessionReply(cloves, target, state, re.tag, keyManager, callback);
         }
         if (_log.shouldDebug())
             _log.debug("Encrypting as ES to " + target + " with key " + re.key + " and tag " + re.tag.toBase64());
-        byte rv[] = encryptExistingSession(cloves, target, re, replyDI, callback, keyManager);
+        byte rv[] = encryptExistingSession(cloves, target, re, callback, keyManager);
         return rv;
     }
 
@@ -633,12 +629,11 @@ public final class ECIESAEADEngine {
      *  - 16 byte MAC
      * </pre>
      *
-     * @param replyDI non-null to request an ack, or null
      * @param callback may be null
      * @return encrypted data or null on failure
      */
     private byte[] encryptNewSession(CloveSet cloves, PublicKey target, PrivateKey priv,
-                                     RatchetSKM keyManager, DeliveryInstructions replyDI,
+                                     RatchetSKM keyManager,
                                      ReplyCallback callback) {
         HandshakeState state;
         try {
@@ -653,7 +648,7 @@ public final class ECIESAEADEngine {
         if (_log.shouldDebug())
             _log.debug("State before encrypt new session: " + state);
 
-        byte[] payload = createPayload(cloves, cloves.getExpiration(), replyDI, null, null);
+        byte[] payload = createPayload(cloves, cloves.getExpiration(), false, null, null);
 
         byte[] enc = new byte[KEYLEN + KEYLEN + MACLEN + payload.length + MACLEN];
         try {
@@ -699,13 +694,12 @@ public final class ECIESAEADEngine {
      * </pre>
      *
      * @param state must have already been cloned
-     * @param replyDI non-null to request an ack, or null
      * @param callback may be null
      * @return encrypted data or null on failure
      */
     private byte[] encryptNewSessionReply(CloveSet cloves, PublicKey target, HandshakeState state,
                                           RatchetSessionTag currentTag, RatchetSKM keyManager,
-                                          DeliveryInstructions replyDI, ReplyCallback callback) {
+                                          ReplyCallback callback) {
         if (_log.shouldDebug())
             _log.debug("State before encrypt new session reply: " + state);
         byte[] tag = currentTag.getData();
@@ -713,7 +707,7 @@ public final class ECIESAEADEngine {
         if (_log.shouldDebug())
             _log.debug("State after mixhash tag before encrypt new session reply: " + state);
 
-        byte[] payload = createPayload(cloves, 0, replyDI, null, null);
+        byte[] payload = createPayload(cloves, 0, false, null, null);
 
         // part 1 - tag and empty payload
         byte[] enc = new byte[TAGLEN + KEYLEN + MACLEN + payload.length + MACLEN];
@@ -773,17 +767,14 @@ public final class ECIESAEADEngine {
      * </pre>
      *
      * @param target only used if callback is non-null to register it
-     * @param replyDI non-null to request an ack, or null
      * @return encrypted data or null on failure
      */
     private byte[] encryptExistingSession(CloveSet cloves, PublicKey target, RatchetEntry re,
-                                          DeliveryInstructions replyDI, ReplyCallback callback,
+                                          ReplyCallback callback,
                                           RatchetSKM keyManager) {
-        // TODO remove DI, just make it a boolean
-        if (ACKREQ_IN_ES && replyDI == null)
-            replyDI = new DeliveryInstructions();
+        boolean ackreq = callback != null || ACKREQ_IN_ES;
         byte rawTag[] = re.tag.getData();
-        byte[] payload = createPayload(cloves, 0, replyDI, re.nextKey, re.acksToSend);
+        byte[] payload = createPayload(cloves, 0, ackreq, re.nextKey, re.acksToSend);
         SessionKeyAndNonce key = re.key;
         int nonce = key.getNonce();
         byte encr[] = encryptAEADBlock(rawTag, payload, key, nonce);
@@ -813,7 +804,7 @@ public final class ECIESAEADEngine {
      */
     public byte[] encrypt(CloveSet cloves, SessionKey key, RatchetSessionTag tag) {
         byte rawTag[] = tag.getData();
-        byte[] payload = createPayload(cloves, 0, null, null, null);
+        byte[] payload = createPayload(cloves, 0, false, null, null);
         byte encr[] = encryptAEADBlock(rawTag, payload, key, 0);
         System.arraycopy(rawTag, 0, encr, 0, TAGLEN);
         return encr;
@@ -917,9 +908,9 @@ public final class ECIESAEADEngine {
                 _log.warn("ACK in NS/NSR?");
         }
 
-        public void gotAckRequest(int id, DeliveryInstructions di) {
+        public void gotAckRequest() {
             if (_log.shouldDebug())
-                _log.debug("Got ACK REQUEST block: " + id + " / " + di);
+                _log.debug("Got ACK REQUEST block");
             ackRequested = true;
         }
 
@@ -941,17 +932,17 @@ public final class ECIESAEADEngine {
 
     /**
      *  @param expiration if greater than zero, add a DateTime block
-     *  @param replyDI non-null to request an ack, or null
+     *  @param ackreq to request an ack, must be false for NS/NSR
      *  @param acksTOSend may be null
      */
     private byte[] createPayload(CloveSet cloves, long expiration,
-                                 DeliveryInstructions replyDI, NextSessionKey nextKey,
+                                 boolean ackreq, NextSessionKey nextKey,
                                  List<Integer> acksToSend) {
         int count = cloves.getCloveCount();
         int numblocks = count + 1;
         if (expiration > 0)
             numblocks++;
-        if (replyDI != null)
+        if (ackreq)
             numblocks++;
         if (nextKey != null)
             numblocks++;
@@ -975,10 +966,9 @@ public final class ECIESAEADEngine {
             blocks.add(block);
             len += block.getTotalLength();
         }
-        if (replyDI != null) {
+        if (ackreq) {
             // put after the cloves so recipient has any LS garlic
-            // ignore actual DI
-            Block block = new AckRequestBlock(0, null);
+            Block block = new AckRequestBlock();
             blocks.add(block);
             len += block.getTotalLength();
         }

router/java/src/net/i2p/router/crypto/ratchet/RatchetPayload.java

@@ -8,7 +8,6 @@ import java.util.List;
 import net.i2p.I2PAppContext;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
-import net.i2p.data.i2np.DeliveryInstructions;
 import net.i2p.data.i2np.GarlicClove;
 import net.i2p.data.i2np.GarlicMessage;
 import net.i2p.data.i2np.I2NPMessage;
@@ -32,8 +31,8 @@ class RatchetPayload {
     private static final int BLOCK_OPTIONS = 5;
     private static final int BLOCK_MSGNUM = 6;
     private static final int BLOCK_NEXTKEY = 7;
-    private static final int BLOCK_ACKKEY = 8;
-    private static final int BLOCK_REPLYDI = 9;
+    private static final int BLOCK_ACK = 8;
+    private static final int BLOCK_ACKREQ = 9;
     private static final int BLOCK_GARLIC = 11;
     private static final int BLOCK_PADDING = 254;
 
@@ -71,7 +70,7 @@ class RatchetPayload {
          *  @param di may be null
          *  @since 0.9.46
          */
-        public void gotAckRequest(int id, DeliveryInstructions di);
+        public void gotAckRequest();
 
         /**
          *  For stats.
@@ -154,10 +153,10 @@ class RatchetPayload {
                   }
                     break;
 
-                case BLOCK_ACKKEY:
+                case BLOCK_ACK:
                   {
                     if (len < 4 || (len % 4) != 0)
-                        throw new IOException("Bad length for ACKKEY: " + len);
+                        throw new IOException("Bad length for ACK: " + len);
                     for (int j = i; j < i + len; j += 4) {
                         int id = (int) DataHelper.fromLong(payload, j, 2);
                         int n = (int) DataHelper.fromLong(payload, j + 2, 2);
@@ -166,20 +165,10 @@ class RatchetPayload {
                   }
                     break;
 
-                case BLOCK_REPLYDI:
-                  {
-                    if (len < 3)
-                        throw new IOException("Bad length for REPLYDI: " + len);
-                    int id = (int) DataHelper.fromLong(payload, i, 2);
-                    DeliveryInstructions di;
-                    if ((payload[2] & 0x01) != 0) {
-                        di = new DeliveryInstructions();
-                        di.readBytes(payload, i + 3);
-                    } else {
-                        di = null;
-                    }
-                    cb.gotAckRequest(id, di);
-                  }
+                case BLOCK_ACKREQ:
+                    if (len < 1)
+                        throw new IOException("Bad length for ACKREQ: " + len);
+                    cb.gotAckRequest();
                     break;
 
                 case BLOCK_TERMINATION:
@@ -384,7 +373,7 @@ class RatchetPayload {
         private final byte[] data;
 
         public AckBlock(int keyID, int n) {
-            super(BLOCK_ACKKEY);
+            super(BLOCK_ACK);
             data = new byte[4];
             DataHelper.toLong(data, 0, 2, keyID);
             DataHelper.toLong(data, 2, 2, n);
@@ -394,7 +383,7 @@ class RatchetPayload {
          *  @param acks each is id &lt;&lt; 16 | n
          */
         public AckBlock(List<Integer> acks) {
-            super(BLOCK_ACKKEY);
+            super(BLOCK_ACK);
             data = new byte[4 * acks.size()];
             int i = 0;
             for (Integer a : acks) {
@@ -417,33 +406,19 @@ class RatchetPayload {
      *  @since 0.9.46
      */
     public static class AckRequestBlock extends Block {
-        private final byte[] data;
 
-        /**
-         *  @param sessionID 0 - 65535
-         *  @param di may be null
-         */
-        public AckRequestBlock(int sessionID, DeliveryInstructions di) {
-            super(BLOCK_REPLYDI);
-            int len = 3;
-            if (di != null)
-                len += di.getSize();
-            data = new byte[len];
-            DataHelper.toLong(data, 0, 2, sessionID);
-            if (di != null) {
-                data[2] = 0x01;
-                di.writeBytes(data, 3);
-            }
-            // else flag is zero
+        public AckRequestBlock() {
+            super(BLOCK_ACKREQ);
+            // flag is zero
         }
 
         public int getDataLength() {
-            return data.length;
+            return 1;
         }
 
         public int writeData(byte[] tgt, int off) {
-            System.arraycopy(data, 0, tgt, off, data.length);
-            return off + data.length;
+            tgt[off] = 0;
+            return off + 1;
         }
     }
 

router/java/src/net/i2p/router/message/GarlicMessageBuilder.java

@@ -277,7 +277,6 @@ public class GarlicMessageBuilder {
      * @param config how/what to wrap
      * @param target public key of the location being garlic routed to (may be null if we 
      *               know the encryptKey and encryptTag)
-     * @param replyDI non-null to request an ack, or null
      * @param callback may be null
      * @return null if expired or on other errors
      * @throws IllegalArgumentException on error
@@ -285,7 +284,7 @@ public class GarlicMessageBuilder {
      */
     static GarlicMessage buildECIESMessage(RouterContext ctx, GarlicConfig config,
                                            PublicKey target, Hash from, SessionKeyManager skm,
-                                           DeliveryInstructions replyDI, ReplyCallback callback) {
+                                           ReplyCallback callback) {
         PublicKey key = config.getRecipientPublicKey();
         if (key.getType() != EncType.ECIES_X25519)
             throw new IllegalArgumentException();
@@ -315,7 +314,7 @@ public class GarlicMessageBuilder {
                 log.warn("No SKM for " + from.toBase32());
             return null;
         }
-        byte encData[] = ctx.eciesEngine().encrypt(cloveSet, target, priv, rskm, replyDI, callback);
+        byte encData[] = ctx.eciesEngine().encrypt(cloveSet, target, priv, rskm, callback);
         if (encData == null) {
             if (log.shouldWarn())
                 log.warn("Encrypt fail for " + from.toBase32());

router/java/src/net/i2p/router/message/OutboundClientMessageJobHelper.java

@@ -130,27 +130,7 @@ class OutboundClientMessageJobHelper {
             return null;
         GarlicMessage msg;
         if (isECIES) {
-            DeliveryInstructions di;
-            if (requireAck) {
-                // setup reply DI
-                di = new DeliveryInstructions();
-                if (bundledReplyLeaseSet != null) {
-                    di.setDeliveryMode(DeliveryInstructions.DELIVERY_MODE_DESTINATION);
-                    di.setDestination(from);
-                } else if (replyTunnel != null) {
-                    di.setDeliveryMode(DeliveryInstructions.DELIVERY_MODE_TUNNEL);
-                    TunnelId replyToTunnelId = replyTunnel.getReceiveTunnelId(0);
-                    Hash replyToTunnelRouter = replyTunnel.getPeer(0);
-                    di.setRouter(replyToTunnelRouter);
-                    di.setTunnelId(replyToTunnelId);
-                } else {
-                    // shouldn't happen
-                    di = null;
-                }
-            } else {
-                di = null;
-            }
-            msg = GarlicMessageBuilder.buildECIESMessage(ctx, config, recipientPK, from, skm, di, callback);
+            msg = GarlicMessageBuilder.buildECIESMessage(ctx, config, recipientPK, from, skm, callback);
         } else {
             // no use sending tags unless we have a reply token set up already
             int tagsToSend = replyToken >= 0 ? (tagsToSendOverride > 0 ? tagsToSendOverride : skm.getTagsToSend()) : 0;