The POW callback is now a service and its state stored.

The proof of work engine therefore just has to remember its initial hash making server based POW easier.

demo/src/main/java/ch/dissem/bitmessage/demo/Application.java

@@ -22,10 +22,7 @@ import ch.dissem.bitmessage.entity.Plaintext;
 import ch.dissem.bitmessage.entity.payload.Pubkey;
 import ch.dissem.bitmessage.networking.DefaultNetworkHandler;
 import ch.dissem.bitmessage.ports.MemoryNodeRegistry;
-import ch.dissem.bitmessage.repository.JdbcAddressRepository;
+import ch.dissem.bitmessage.repository.*;
-import ch.dissem.bitmessage.repository.JdbcConfig;
-import ch.dissem.bitmessage.repository.JdbcInventory;
-import ch.dissem.bitmessage.repository.JdbcMessageRepository;
 import ch.dissem.bitmessage.security.bc.BouncySecurity;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -50,6 +47,7 @@ public class Application {
                 .inventory(new JdbcInventory(jdbcConfig))
                 .nodeRegistry(new MemoryNodeRegistry())
                 .messageRepo(new JdbcMessageRepository(jdbcConfig))
+                .powRepo(new JdbcProofOfWorkRepository(jdbcConfig))
                 .networkHandler(new DefaultNetworkHandler())
                 .security(new BouncySecurity())
                 .port(48444)

demo/src/main/java/ch/dissem/bitmessage/demo/Main.java

@@ -51,6 +51,7 @@ public class Main {
                     .inventory(new JdbcInventory(jdbcConfig))
                     .nodeRegistry(new MemoryNodeRegistry())
                     .messageRepo(new JdbcMessageRepository(jdbcConfig))
+                    .powRepo(new JdbcProofOfWorkRepository(jdbcConfig))
                     .networkHandler(new DefaultNetworkHandler())
                     .security(new BouncySecurity())
                     .port(48444)

domain/src/main/java/ch/dissem/bitmessage/BitmessageContext.java

@@ -75,7 +75,7 @@ public class BitmessageContext {
     }
 
     public AddressRepository addresses() {
-        return ctx.getAddressRepo();
+        return ctx.getAddressRepository();
     }
 
     public MessageRepository messages() {
@@ -90,7 +90,7 @@ public class BitmessageContext {
                 ctx.getNetworkExtraBytes(),
                 features
         ));
-        ctx.getAddressRepo().save(identity);
+        ctx.getAddressRepository().save(identity);
         pool.submit(new Runnable() {
             @Override
             public void run() {
@@ -102,6 +102,7 @@ public class BitmessageContext {
 
     public void addDistributedMailingList(String address, String alias) {
         // TODO
+        throw new RuntimeException("not implemented");
     }
 
     public void broadcast(final BitmessageAddress from, final String subject, final String message) {
@@ -120,9 +121,7 @@ public class BitmessageContext {
                         from,
                         from,
                         Factory.getBroadcast(from, msg),
-                        +2 * DAY,
+                        +2 * DAY
-                        0,
-                        0
                 );
                 msg.setStatus(SENT);
                 msg.addLabels(ctx.getMessageRepository().getLabels(Label.Type.BROADCAST, Label.Type.SENT));
@@ -159,9 +158,7 @@ public class BitmessageContext {
                             from,
                             to,
                             new Msg(msg),
-                            +2 * DAY,
+                            +2 * DAY
-                            ctx.getNonceTrialsPerByte(to),
-                            ctx.getExtraBytes(to)
                     );
                     msg.setStatus(SENT);
                     msg.addLabels(ctx.getMessageRepository().getLabels(Label.Type.SENT));
@@ -176,9 +173,7 @@ public class BitmessageContext {
                 requestingIdentity,
                 address,
                 new GetPubkey(address),
-                +28 * DAY,
+                +28 * DAY
-                ctx.getNetworkNonceTrialsPerByte(),
-                ctx.getNetworkExtraBytes()
         );
     }
 
@@ -220,7 +215,7 @@ public class BitmessageContext {
     }
 
     public void addContact(BitmessageAddress contact) {
-        ctx.getAddressRepo().save(contact);
+        ctx.getAddressRepository().save(contact);
         tryToFindMatchingPubkey(contact);
         if (contact.getPubkey() == null) {
             ctx.requestPubkey(contact);
@@ -237,7 +232,7 @@ public class BitmessageContext {
                         v4Pubkey.decrypt(address.getPublicDecryptionKey());
                         if (object.isSignatureValid(v4Pubkey)) {
                             address.setPubkey(v4Pubkey);
-                            ctx.getAddressRepo().save(address);
+                            ctx.getAddressRepository().save(address);
                             break;
                         } else {
                             LOG.info("Found pubkey for " + address + " but signature is invalid");
@@ -246,7 +241,7 @@ public class BitmessageContext {
                 } else {
                     if (Arrays.equals(pubkey.getRipe(), address.getRipe())) {
                         address.setPubkey(pubkey);
-                        ctx.getAddressRepo().save(address);
+                        ctx.getAddressRepository().save(address);
                         break;
                     }
                 }
@@ -258,7 +253,7 @@ public class BitmessageContext {
 
     public void addSubscribtion(BitmessageAddress address) {
         address.setSubscribed(true);
-        ctx.getAddressRepo().save(address);
+        ctx.getAddressRepository().save(address);
         tryToFindBroadcastsForAddress(address);
     }
 
@@ -292,6 +287,7 @@ public class BitmessageContext {
         NetworkHandler networkHandler;
         AddressRepository addressRepo;
         MessageRepository messageRepo;
+        ProofOfWorkRepository proofOfWorkRepository;
         ProofOfWorkEngine proofOfWorkEngine;
         Security security;
         MessageCallback messageCallback;
@@ -333,6 +329,11 @@ public class BitmessageContext {
             return this;
         }
 
+        public Builder powRepo(ProofOfWorkRepository proofOfWorkRepository) {
+            this.proofOfWorkRepository = proofOfWorkRepository;
+            return this;
+        }
+
         public Builder security(Security security) {
             this.security = security;
             return this;
@@ -374,6 +375,7 @@ public class BitmessageContext {
             nonNull("networkHandler", networkHandler);
             nonNull("addressRepo", addressRepo);
             nonNull("messageRepo", messageRepo);
+            nonNull("proofOfWorkRepo", proofOfWorkRepository);
             if (proofOfWorkEngine == null) {
                 proofOfWorkEngine = new MultiThreadedPOWEngine();
             }

domain/src/main/java/ch/dissem/bitmessage/DefaultMessageListener.java

@@ -69,7 +69,7 @@ class DefaultMessageListener implements NetworkHandler.MessageListener {
     }
 
     protected void receive(ObjectMessage object, GetPubkey getPubkey) {
-        BitmessageAddress identity = ctx.getAddressRepo().findIdentity(getPubkey.getRipeTag());
+        BitmessageAddress identity = ctx.getAddressRepository().findIdentity(getPubkey.getRipeTag());
         if (identity != null && identity.getPrivateKey() != null) {
             LOG.info("Got pubkey request for identity " + identity);
             // FIXME: only send pubkey if it wasn't sent in the last 28 days
@@ -82,17 +82,17 @@ class DefaultMessageListener implements NetworkHandler.MessageListener {
         try {
             if (pubkey instanceof V4Pubkey) {
                 V4Pubkey v4Pubkey = (V4Pubkey) pubkey;
-                address = ctx.getAddressRepo().findContact(v4Pubkey.getTag());
+                address = ctx.getAddressRepository().findContact(v4Pubkey.getTag());
                 if (address != null) {
                     v4Pubkey.decrypt(address.getPublicDecryptionKey());
                 }
             } else {
-                address = ctx.getAddressRepo().findContact(pubkey.getRipe());
+                address = ctx.getAddressRepository().findContact(pubkey.getRipe());
             }
             if (address != null) {
                 address.setPubkey(pubkey);
                 LOG.info("Got pubkey for contact " + address);
-                ctx.getAddressRepo().save(address);
+                ctx.getAddressRepository().save(address);
                 List<Plaintext> messages = ctx.getMessageRepository().findMessages(Plaintext.Status.PUBKEY_REQUESTED, address);
                 LOG.info("Sending " + messages.size() + " messages for contact " + address);
                 for (Plaintext msg : messages) {
@@ -102,9 +102,7 @@ class DefaultMessageListener implements NetworkHandler.MessageListener {
                             msg.getFrom(),
                             msg.getTo(),
                             new Msg(msg),
-                            +2 * DAY,
+                            +2 * DAY
-                            ctx.getNonceTrialsPerByte(msg.getTo()),
-                            ctx.getExtraBytes(msg.getTo())
                     );
                     msg.setStatus(SENT);
                     ctx.getMessageRepository().save(msg);
@@ -115,7 +113,7 @@ class DefaultMessageListener implements NetworkHandler.MessageListener {
     }
 
     protected void receive(ObjectMessage object, Msg msg) throws IOException {
-        for (BitmessageAddress identity : ctx.getAddressRepo().getIdentities()) {
+        for (BitmessageAddress identity : ctx.getAddressRepository().getIdentities()) {
             try {
                 msg.decrypt(identity.getPrivateKey().getPrivateEncryptionKey());
                 msg.getPlaintext().setTo(identity);
@@ -136,7 +134,7 @@ class DefaultMessageListener implements NetworkHandler.MessageListener {
 
     protected void receive(ObjectMessage object, Broadcast broadcast) throws IOException {
         byte[] tag = broadcast instanceof V5Broadcast ? ((V5Broadcast) broadcast).getTag() : null;
-        for (BitmessageAddress subscription : ctx.getAddressRepo().getSubscriptions(broadcast.getVersion())) {
+        for (BitmessageAddress subscription : ctx.getAddressRepository().getSubscriptions(broadcast.getVersion())) {
             if (tag != null && !Arrays.equals(tag, subscription.getTag())) {
                 continue;
             }

domain/src/main/java/ch/dissem/bitmessage/InternalContext.java

@@ -48,9 +48,11 @@ public class InternalContext {
     private final NetworkHandler networkHandler;
     private final AddressRepository addressRepository;
     private final MessageRepository messageRepository;
+    private final ProofOfWorkRepository proofOfWorkRepository;
     private final ProofOfWorkEngine proofOfWorkEngine;
     private final MessageCallback messageCallback;
     private final CustomCommandHandler customCommandHandler;
+    private final ProofOfWorkService proofOfWorkService;
 
     private final TreeSet<Long> streams = new TreeSet<>();
     private final int port;
@@ -67,6 +69,8 @@ public class InternalContext {
         this.networkHandler = builder.networkHandler;
         this.addressRepository = builder.addressRepo;
         this.messageRepository = builder.messageRepo;
+        this.proofOfWorkRepository = builder.proofOfWorkRepository;
+        this.proofOfWorkService = new ProofOfWorkService();
         this.proofOfWorkEngine = builder.proofOfWorkEngine;
         this.clientNonce = security.randomNonce();
         this.messageCallback = builder.messageCallback;
@@ -88,7 +92,9 @@ public class InternalContext {
             streams.add(1L);
         }
 
-        init(security, inventory, nodeRegistry, networkHandler, addressRepository, messageRepository, proofOfWorkEngine);
+        init(security, inventory, nodeRegistry, networkHandler, addressRepository, messageRepository,
+                proofOfWorkRepository, proofOfWorkService, proofOfWorkEngine,
+                messageCallback, customCommandHandler);
         for (BitmessageAddress identity : addressRepository.getIdentities()) {
             streams.add(identity.getStream());
         }
@@ -118,7 +124,7 @@ public class InternalContext {
         return networkHandler;
     }
 
-    public AddressRepository getAddressRepo() {
+    public AddressRepository getAddressRepository() {
         return addressRepository;
     }
 
@@ -126,6 +132,10 @@ public class InternalContext {
         return messageRepository;
     }
 
+    public ProofOfWorkRepository getProofOfWorkRepository() {
+        return proofOfWorkRepository;
+    }
+
     public ProofOfWorkEngine getProofOfWorkEngine() {
         return proofOfWorkEngine;
     }
@@ -147,22 +157,12 @@ public class InternalContext {
         return networkNonceTrialsPerByte;
     }
 
-    public long getNonceTrialsPerByte(BitmessageAddress address) {
-        long nonceTrialsPerByte = address.getPubkey().getNonceTrialsPerByte();
-        return networkNonceTrialsPerByte > nonceTrialsPerByte ? networkNonceTrialsPerByte : nonceTrialsPerByte;
-    }
-
     public long getNetworkExtraBytes() {
         return networkExtraBytes;
     }
 
-    public long getExtraBytes(BitmessageAddress address) {
-        long extraBytes = address.getPubkey().getExtraBytes();
-        return networkExtraBytes > extraBytes ? networkExtraBytes : extraBytes;
-    }
-
     public void send(final BitmessageAddress from, BitmessageAddress to, final ObjectPayload payload,
-                     final long timeToLive, final long nonceTrialsPerByte, final long extraBytes) {
+                     final long timeToLive) {
         try {
             if (to == null) to = from;
             long expires = UnixTime.now(+timeToLive);
@@ -181,22 +181,7 @@ public class InternalContext {
                 object.encrypt(to.getPubkey());
             }
             messageCallback.proofOfWorkStarted(payload);
-            security.doProofOfWork(object, nonceTrialsPerByte, extraBytes,
+            proofOfWorkService.doProofOfWork(to, object);
-                    new ProofOfWorkEngine.Callback() {
-                        @Override
-                        public void onNonceCalculated(byte[] nonce) {
-                            object.setNonce(nonce);
-                            messageCallback.proofOfWorkCompleted(payload);
-                            if (payload instanceof PlaintextHolder) {
-                                Plaintext plaintext = ((PlaintextHolder) payload).getPlaintext();
-                                plaintext.setInventoryVector(object.getInventoryVector());
-                                messageRepository.save(plaintext);
-                            }
-                            inventory.storeObject(object);
-                            networkHandler.offer(object.getInventoryVector());
-                            messageCallback.messageOffered(payload, object.getInventoryVector());
-                        }
-                    });
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
@@ -214,18 +199,8 @@ public class InternalContext {
             response.sign(identity.getPrivateKey());
             response.encrypt(security.createPublicKey(identity.getPublicDecryptionKey()));
             messageCallback.proofOfWorkStarted(identity.getPubkey());
-            security.doProofOfWork(response, networkNonceTrialsPerByte, networkExtraBytes,
+            // TODO: remember that the pubkey is just about to be sent, and on which stream!
-                    new ProofOfWorkEngine.Callback() {
+            proofOfWorkService.doProofOfWork(response);
-                        @Override
-                        public void onNonceCalculated(byte[] nonce) {
-                            response.setNonce(nonce);
-                            messageCallback.proofOfWorkCompleted(identity.getPubkey());
-                            inventory.storeObject(response);
-                            networkHandler.offer(response.getInventoryVector());
-                            // TODO: save that the pubkey was just sent, and on which stream!
-                            messageCallback.messageOffered(identity.getPubkey(), response.getInventoryVector());
-                        }
-                    });
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
@@ -240,17 +215,7 @@ public class InternalContext {
                 .payload(new GetPubkey(contact))
                 .build();
         messageCallback.proofOfWorkStarted(response.getPayload());
-        security.doProofOfWork(response, networkNonceTrialsPerByte, networkExtraBytes,
+        proofOfWorkService.doProofOfWork(response);
-                new ProofOfWorkEngine.Callback() {
-                    @Override
-                    public void onNonceCalculated(byte[] nonce) {
-                        response.setNonce(nonce);
-                        messageCallback.proofOfWorkCompleted(response.getPayload());
-                        inventory.storeObject(response);
-                        networkHandler.offer(response.getInventoryVector());
-                        messageCallback.messageOffered(response.getPayload(), response.getInventoryVector());
-                    }
-                });
     }
 
     public long getClientNonce() {

domain/src/main/java/ch/dissem/bitmessage/ProofOfWorkService.java

@@ -0,0 +1,62 @@
+package ch.dissem.bitmessage;
+
+import ch.dissem.bitmessage.entity.BitmessageAddress;
+import ch.dissem.bitmessage.entity.ObjectMessage;
+import ch.dissem.bitmessage.entity.Plaintext;
+import ch.dissem.bitmessage.entity.PlaintextHolder;
+import ch.dissem.bitmessage.ports.MessageRepository;
+import ch.dissem.bitmessage.ports.ProofOfWorkEngine;
+import ch.dissem.bitmessage.ports.ProofOfWorkRepository;
+import ch.dissem.bitmessage.ports.Security;
+
+import static ch.dissem.bitmessage.utils.Singleton.security;
+
+/**
+ * @author Christian Basler
+ */
+public class ProofOfWorkService implements ProofOfWorkEngine.Callback, InternalContext.ContextHolder {
+    private Security security;
+    private InternalContext ctx;
+    private ProofOfWorkRepository powRepo;
+    private MessageRepository messageRepo;
+
+    public void doProofOfWork(ObjectMessage object) {
+        doProofOfWork(null, object);
+    }
+
+    public void doProofOfWork(BitmessageAddress recipient, ObjectMessage object) {
+        long nonceTrialsPerByte = recipient == null ? 0 : recipient.getPubkey().getNonceTrialsPerByte();
+        long extraBytes = recipient == null ? 0 : recipient.getPubkey().getExtraBytes();
+
+        powRepo.putObject(object, nonceTrialsPerByte, extraBytes);
+        if (object.getPayload() instanceof PlaintextHolder){
+            Plaintext plaintext = ((PlaintextHolder) object.getPayload()).getPlaintext();
+            plaintext.setInitialHash(security.getInitialHash(object));
+            messageRepo.save(plaintext);
+        }
+        security.doProofOfWork(object, nonceTrialsPerByte, extraBytes, this);
+    }
+
+    @Override
+    public void onNonceCalculated(byte[] initialHash, byte[] nonce) {
+        ObjectMessage object = powRepo.getObject(initialHash);
+        object.setNonce(nonce);
+//        messageCallback.proofOfWorkCompleted(payload);
+        Plaintext plaintext = messageRepo.getMessage(initialHash);
+        if (plaintext != null) {
+            plaintext.setInventoryVector(object.getInventoryVector());
+            messageRepo.save(plaintext);
+        }
+        ctx.getInventory().storeObject(object);
+        ctx.getNetworkHandler().offer(object.getInventoryVector());
+//        messageCallback.messageOffered(payload, object.getInventoryVector());
+    }
+
+    @Override
+    public void setContext(InternalContext ctx) {
+        this.ctx = ctx;
+        this.security = security();
+        this.powRepo = ctx.getProofOfWorkRepository();
+        this.messageRepo = ctx.getMessageRepository();
+    }
+}

domain/src/main/java/ch/dissem/bitmessage/entity/CustomMessage.java

@@ -16,26 +16,36 @@
 
 package ch.dissem.bitmessage.entity;
 
+import ch.dissem.bitmessage.utils.AccessCounter;
+import ch.dissem.bitmessage.utils.Encode;
+
 import java.io.*;
 
 import static ch.dissem.bitmessage.utils.Decode.bytes;
+import static ch.dissem.bitmessage.utils.Decode.varString;
 
 /**
  * @author Christian Basler
  */
 public class CustomMessage implements MessagePayload {
+    public static final String COMMAND_ERROR = "ERROR";
+
+    private final String command;
     private final byte[] data;
 
-    public CustomMessage() {
+    public CustomMessage(String command) {
+        this.command = command;
         this.data = null;
     }
 
-    public CustomMessage(byte[] data) {
+    public CustomMessage(String command, byte[] data) {
+        this.command = command;
         this.data = data;
     }
 
     public static MessagePayload read(InputStream in, int length) throws IOException {
-        return new CustomMessage(bytes(in, length));
+        AccessCounter counter = new AccessCounter();
+        return new CustomMessage(varString(in, counter), bytes(in, length - counter.length()));
     }
 
     @Override
@@ -56,6 +66,7 @@ public class CustomMessage implements MessagePayload {
     @Override
     public void write(OutputStream out) throws IOException {
         if (data != null) {
+            Encode.varString(command, out);
             out.write(data);
         } else {
             throw new RuntimeException("Tried to write custom message without data. " +
@@ -63,9 +74,13 @@ public class CustomMessage implements MessagePayload {
         }
     }
 
+    public boolean isError() {
+        return COMMAND_ERROR.equals(command);
+    }
+
     public static CustomMessage error(String message) {
         try {
-            return new CustomMessage(("ERROR\n" + message).getBytes("UTF-8"));
+            return new CustomMessage(COMMAND_ERROR, message.getBytes("UTF-8"));
         } catch (UnsupportedEncodingException e) {
             throw new RuntimeException(e);
         }

domain/src/main/java/ch/dissem/bitmessage/entity/ObjectMessage.java

@@ -156,7 +156,11 @@ public class ObjectMessage implements MessagePayload {
 
     @Override
     public void write(OutputStream out) throws IOException {
+        if (nonce != null) {
             out.write(nonce);
+        } else {
+            out.write(new byte[8]);
+        }
         out.write(getPayloadBytesWithoutNonce());
     }
 

domain/src/main/java/ch/dissem/bitmessage/entity/Plaintext.java

@@ -44,6 +44,7 @@ public class Plaintext implements Streamable {
     private Long received;
 
     private Set<Label> labels;
+    private byte[] initialHash;
 
     private Plaintext(Builder builder) {
         id = builder.id;
@@ -260,6 +261,14 @@ public class Plaintext implements Streamable {
         }
     }
 
+    public void setInitialHash(byte[] initialHash) {
+        this.initialHash = initialHash;
+    }
+
+    public byte[] getInitialHash() {
+        return initialHash;
+    }
+
     public enum Encoding {
         IGNORE(0), TRIVIAL(1), SIMPLE(2);
 

domain/src/main/java/ch/dissem/bitmessage/ports/AbstractSecurity.java

@@ -34,6 +34,8 @@ import java.security.GeneralSecurityException;
 import java.security.MessageDigest;
 import java.security.SecureRandom;
 
+import static ch.dissem.bitmessage.utils.Numbers.max;
+
 /**
  * Implements everything that isn't directly dependent on either Spongy- or Bouncycastle.
  */
@@ -95,8 +97,8 @@ public abstract class AbstractSecurity implements Security, InternalContext.Cont
     public void doProofOfWork(ObjectMessage object, long nonceTrialsPerByte,
                               long extraBytes, ProofOfWorkEngine.Callback callback) {
         try {
-            if (nonceTrialsPerByte < 1000) nonceTrialsPerByte = 1000;
+            nonceTrialsPerByte = max(nonceTrialsPerByte, context.getNetworkNonceTrialsPerByte());
-            if (extraBytes < 1000) extraBytes = 1000;
+            extraBytes = max(extraBytes, context.getNetworkExtraBytes());
 
             byte[] initialHash = getInitialHash(object);
 
@@ -117,7 +119,8 @@ public abstract class AbstractSecurity implements Security, InternalContext.Cont
         }
     }
 
-    private byte[] getInitialHash(ObjectMessage object) throws IOException {
+    @Override
+    public byte[] getInitialHash(ObjectMessage object) {
         return sha512(object.getPayloadBytesWithoutNonce());
     }
 

domain/src/main/java/ch/dissem/bitmessage/ports/MessageRepository.java

@@ -30,6 +30,8 @@ public interface MessageRepository {
 
     int countUnread(Label label);
 
+    Plaintext getMessage(byte[] initialHash);
+
     List<Plaintext> findMessages(Label label);
 
     List<Plaintext> findMessages(Status status);

domain/src/main/java/ch/dissem/bitmessage/ports/MultiThreadedPOWEngine.java

@@ -102,7 +102,7 @@ public class MultiThreadedPOWEngine implements ProofOfWorkEngine {
                     synchronized (callback) {
                         if (!Thread.interrupted()) {
                             try {
-                                callback.onNonceCalculated(nonce);
+                                callback.onNonceCalculated(initialHash, nonce);
                             } finally {
                                 semaphore.release();
                                 for (Worker w : workers) {
@@ -128,12 +128,12 @@ public class MultiThreadedPOWEngine implements ProofOfWorkEngine {
         }
 
         @Override
-        public void onNonceCalculated(byte[] nonce) {
+        public void onNonceCalculated(byte[] initialHash, byte[] nonce) {
             synchronized (this) {
                 if (waiting) {
                     LOG.info("Nonce calculated in " + ((System.currentTimeMillis() - startTime) / 1000) + " seconds");
                     waiting = false;
-                    callback.onNonceCalculated(nonce);
+                    callback.onNonceCalculated(initialHash, nonce);
                 }
             }
         }

domain/src/main/java/ch/dissem/bitmessage/ports/ProofOfWorkEngine.java

@@ -35,6 +35,6 @@ public interface ProofOfWorkEngine {
         /**
          * @param nonce 8 bytes nonce
          */
-        void onNonceCalculated(byte[] nonce);
+        void onNonceCalculated(byte[] initialHash, byte[] nonce);
     }
 }

domain/src/main/java/ch/dissem/bitmessage/ports/ProofOfWorkRepository.java

@@ -0,0 +1,16 @@
+package ch.dissem.bitmessage.ports;
+
+import ch.dissem.bitmessage.entity.ObjectMessage;
+
+/**
+ * Objects that proof of work is currently being done for.
+ *
+ * @author Christian Basler
+ */
+public interface ProofOfWorkRepository {
+    ObjectMessage getObject(byte[] initialHash);
+
+    void putObject(ObjectMessage object, long nonceTrialsPerByte, long extraBytes);
+
+    void removeObject(ObjectMessage object);
+}

domain/src/main/java/ch/dissem/bitmessage/ports/Security.java

@@ -134,6 +134,8 @@ public interface Security {
     void checkProofOfWork(ObjectMessage object, long nonceTrialsPerByte, long extraBytes)
             throws IOException;
 
+    byte[] getInitialHash(ObjectMessage object);
+
     /**
      * Calculates the MAC for a message (data)
      *

domain/src/main/java/ch/dissem/bitmessage/ports/SimplePOWEngine.java

@@ -40,6 +40,6 @@ public class SimplePOWEngine implements ProofOfWorkEngine {
             mda.update(nonce);
             mda.update(initialHash);
         } while (Bytes.lt(target, mda.digest(mda.digest()), 8));
-        callback.onNonceCalculated(nonce);
+        callback.onNonceCalculated(initialHash, nonce);
     }
 }

domain/src/main/java/ch/dissem/bitmessage/utils/Decode.java

@@ -130,9 +130,13 @@ public class Decode {
     }
 
     public static String varString(InputStream stream) throws IOException {
-        int length = (int) varInt(stream);
+        return varString(stream, null);
+    }
+
+    public static String varString(InputStream stream, AccessCounter counter) throws IOException {
+        int length = (int) varInt(stream, counter);
         // FIXME: technically, it says the length in characters, but I think this one might be correct
         // otherwise it will get complicated, as we'll need to read UTF-8 char by char...
-        return new String(bytes(stream, length), "utf-8");
+        return new String(bytes(stream, length, counter), "utf-8");
     }
 }

domain/src/main/java/ch/dissem/bitmessage/utils/Numbers.java

@@ -0,0 +1,10 @@
+package ch.dissem.bitmessage.utils;
+
+/**
+ * Created by chrig on 07.12.2015.
+ */
+public class Numbers {
+    public static long max(long a, long b) {
+        return a > b ? a : b;
+    }
+}

domain/src/test/java/ch/dissem/bitmessage/ports/ProofOfWorkEngineTest.java

@@ -43,7 +43,7 @@ public class ProofOfWorkEngineTest extends TestBase {
         engine.calculateNonce(initialHash, target,
                 new ProofOfWorkEngine.Callback() {
                     @Override
-                    public void onNonceCalculated(byte[] nonce) {
+                    public void onNonceCalculated(byte[] initialHash, byte[] nonce) {
                         waiter1.setValue(nonce);
                     }
                 });
@@ -59,7 +59,7 @@ public class ProofOfWorkEngineTest extends TestBase {
         engine.calculateNonce(initialHash2, target2,
                 new ProofOfWorkEngine.Callback() {
                     @Override
-                    public void onNonceCalculated(byte[] nonce) {
+                    public void onNonceCalculated(byte[] initialHash, byte[] nonce) {
                         waiter2.setValue(nonce);
                     }
                 });

extensions/src/main/java/ch/dissem/bitmessage/extensions/CryptoCustomMessage.java

@@ -36,17 +36,20 @@ import static ch.dissem.bitmessage.utils.Singleton.security;
  * @author Christian Basler
  */
 public class CryptoCustomMessage<T extends Streamable> extends CustomMessage {
+    public static final String COMMAND = "ENCRYPTED";
     private final Reader<T> dataReader;
     private CryptoBox container;
     private BitmessageAddress sender;
     private T data;
 
     public CryptoCustomMessage(T data) throws IOException {
+        super(COMMAND);
         this.data = data;
         this.dataReader = null;
     }
 
     private CryptoCustomMessage(CryptoBox container, Reader<T> dataReader) {
+        super(COMMAND);
         this.container = container;
         this.dataReader = dataReader;
     }

repositories/src/main/java/ch/dissem/bitmessage/repository/JdbcMessageRepository.java

@@ -22,6 +22,7 @@ import ch.dissem.bitmessage.entity.Plaintext;
 import ch.dissem.bitmessage.entity.valueobject.InventoryVector;
 import ch.dissem.bitmessage.entity.valueobject.Label;
 import ch.dissem.bitmessage.ports.MessageRepository;
+import ch.dissem.bitmessage.utils.Strings;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -108,6 +109,20 @@ public class JdbcMessageRepository extends JdbcHelper implements MessageReposito
         return 0;
     }
 
+    @Override
+    public Plaintext getMessage(byte[] initialHash) {
+        List<Plaintext> plaintexts = find("initial_hash=X'" + Strings.hex(initialHash) + "'");
+        switch (plaintexts.size()) {
+            case 0:
+                return null;
+            case 1:
+                return plaintexts.get(0);
+            default:
+                throw new RuntimeException("This shouldn't happen, found " + plaintexts.size() +
+                        " messages, one or none was expected");
+        }
+    }
+
     @Override
     public List<Plaintext> findMessages(Label label) {
         return find("id IN (SELECT message_id FROM Message_Label WHERE label_id=" + label.getId() + ")");
@@ -141,8 +156,8 @@ public class JdbcMessageRepository extends JdbcHelper implements MessageReposito
                 long id = rs.getLong("id");
                 builder.id(id);
                 builder.IV(new InventoryVector(iv));
-                builder.from(ctx.getAddressRepo().getAddress(rs.getString("sender")));
+                builder.from(ctx.getAddressRepository().getAddress(rs.getString("sender")));
-                builder.to(ctx.getAddressRepo().getAddress(rs.getString("recipient")));
+                builder.to(ctx.getAddressRepository().getAddress(rs.getString("recipient")));
                 builder.sent(rs.getLong("sent"));
                 builder.received(rs.getLong("received"));
                 builder.status(Plaintext.Status.valueOf(rs.getString("status")));
@@ -173,12 +188,12 @@ public class JdbcMessageRepository extends JdbcHelper implements MessageReposito
     public void save(Plaintext message) {
         // save from address if necessary
         if (message.getId() == null) {
-            BitmessageAddress savedAddress = ctx.getAddressRepo().getAddress(message.getFrom().getAddress());
+            BitmessageAddress savedAddress = ctx.getAddressRepository().getAddress(message.getFrom().getAddress());
             if (savedAddress == null || savedAddress.getPrivateKey() == null) {
                 if (savedAddress != null && savedAddress.getAlias() != null) {
                     message.getFrom().setAlias(savedAddress.getAlias());
                 }
-                ctx.getAddressRepo().save(message.getFrom());
+                ctx.getAddressRepository().save(message.getFrom());
             }
         }
 
@@ -219,7 +234,7 @@ public class JdbcMessageRepository extends JdbcHelper implements MessageReposito
 
     private void insert(Connection connection, Plaintext message) throws SQLException, IOException {
         PreparedStatement ps = connection.prepareStatement(
-                "INSERT INTO Message (iv, type, sender, recipient, data, sent, received, status) VALUES (?, ?, ?, ?, ?, ?, ?, ?)",
+                "INSERT INTO Message (iv, type, sender, recipient, data, sent, received, status, initial_hash) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)",
                 Statement.RETURN_GENERATED_KEYS);
         ps.setBytes(1, message.getInventoryVector() != null ? message.getInventoryVector().getHash() : null);
         ps.setString(2, message.getType().name());
@@ -229,6 +244,7 @@ public class JdbcMessageRepository extends JdbcHelper implements MessageReposito
         ps.setLong(6, message.getSent());
         ps.setLong(7, message.getReceived());
         ps.setString(8, message.getStatus() != null ? message.getStatus().name() : null);
+        ps.setBytes(9, message.getInitialHash());
 
         ps.executeUpdate();
 

repositories/src/main/java/ch/dissem/bitmessage/repository/JdbcProofOfWorkRepository.java

@@ -0,0 +1,69 @@
+package ch.dissem.bitmessage.repository;
+
+import ch.dissem.bitmessage.entity.ObjectMessage;
+import ch.dissem.bitmessage.factory.Factory;
+import ch.dissem.bitmessage.ports.ProofOfWorkRepository;
+import ch.dissem.bitmessage.utils.Strings;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.sql.*;
+
+import static ch.dissem.bitmessage.utils.Singleton.security;
+
+/**
+ * @author Christian Basler
+ */
+public class JdbcProofOfWorkRepository extends JdbcHelper implements ProofOfWorkRepository {
+    private static final Logger LOG = LoggerFactory.getLogger(JdbcProofOfWorkRepository.class);
+
+    public JdbcProofOfWorkRepository(JdbcConfig config) {
+        super(config);
+    }
+
+    @Override
+    public ObjectMessage getObject(byte[] initialHash) {
+        try (Connection connection = config.getConnection()) {
+            PreparedStatement ps = connection.prepareStatement("SELECT data, version FROM POW WHERE initial_hash=?");
+            ps.setBytes(1, initialHash);
+            ResultSet rs = ps.executeQuery();
+            if (rs.next()) {
+                Blob data = rs.getBlob("data");
+                return Factory.getObjectMessage(rs.getInt("version"), data.getBinaryStream(), (int) data.length());
+            } else {
+                throw new RuntimeException("Object requested that we don't have. Initial hash: " + Strings.hex(initialHash));
+            }
+        } catch (Exception e) {
+            LOG.error(e.getMessage(), e);
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public void putObject(ObjectMessage object, long nonceTrialsPerByte, long extraBytes) {
+        try (Connection connection = config.getConnection()) {
+            PreparedStatement ps = connection.prepareStatement("INSERT INTO POW (initial_hash, data, version) VALUES (?, ?, ?)");
+            ps.setBytes(1, security().getInitialHash(object));
+            writeBlob(ps, 2, object);
+            ps.setLong(3, object.getVersion());
+            ps.executeUpdate();
+        } catch (SQLException e) {
+            LOG.debug("Error storing object of type " + object.getPayload().getClass().getSimpleName(), e);
+            throw new RuntimeException(e);
+        } catch (Exception e) {
+            LOG.error(e.getMessage(), e);
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public void removeObject(ObjectMessage object) {
+        try (Connection connection = config.getConnection()) {
+            PreparedStatement ps = connection.prepareStatement("DELETE FROM POW WHERE initial_hash=?");
+            ps.setBytes(1, security().getInitialHash(object));
+            ps.executeUpdate();
+        } catch (SQLException e) {
+            LOG.debug(e.getMessage(), e);
+        }
+    }
+}

repositories/src/main/resources/db/migration/V2.0__Update_table_message.sql

@@ -0,0 +1,2 @@
+ALTER TABLE Message ADD COLUMN initial_hash BINARY(64);
+ALTER TABLE Message ADD CONSTRAINT initial_hash_unique UNIQUE(initial_hash);

repositories/src/main/resources/db/migration/V2.1__Create_table_POW.sql

@@ -0,0 +1,5 @@
+CREATE TABLE POW (
+  initial_hash       BINARY(64)    PRIMARY KEY,
+  data               BLOB          NOT NULL,
+  version            BIGINT        NOT NULL
+);

security-bc/src/test/java/ch/dissem/bitmessage/security/SecurityTest.java

@@ -91,7 +91,7 @@ public class SecurityTest {
         security.doProofOfWork(objectMessage, 1000, 1000,
                 new ProofOfWorkEngine.Callback() {
                     @Override
-                    public void onNonceCalculated(byte[] nonce) {
+                    public void onNonceCalculated(byte[] initialHash, byte[] nonce) {
                         waiter.setValue(nonce);
                     }
                 });