Some code for supporting chans

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

@@ -17,10 +17,7 @@
 package ch.dissem.bitmessage;
 
 import ch.dissem.bitmessage.entity.*;
-import ch.dissem.bitmessage.entity.payload.Broadcast;
+import ch.dissem.bitmessage.entity.payload.*;
-import ch.dissem.bitmessage.entity.payload.Msg;
-import ch.dissem.bitmessage.entity.payload.ObjectPayload;
-import ch.dissem.bitmessage.entity.payload.ObjectType;
 import ch.dissem.bitmessage.entity.payload.Pubkey.Feature;
 import ch.dissem.bitmessage.entity.valueobject.Label;
 import ch.dissem.bitmessage.entity.valueobject.PrivateKey;
@@ -117,9 +114,17 @@ public class BitmessageContext {
         return identity;
     }
 
-    public void addDistributedMailingList(String address, String alias) {
+    public BitmessageAddress joinChan(String passphrase, String address) {
-        // TODO
+        BitmessageAddress chan = BitmessageAddress.chan(address, passphrase);
-        throw new ApplicationException("not implemented");
+        ctx.getAddressRepository().save(chan);
+        return chan;
+    }
+
+    public BitmessageAddress createChan(String passphrase) {
+        // FIXME: hardcoded stream number
+        BitmessageAddress chan = BitmessageAddress.chan(1, passphrase);
+        ctx.getAddressRepository().save(chan);
+        return chan;
     }
 
     public void broadcast(final BitmessageAddress from, final String subject, final String message) {

core/src/main/java/ch/dissem/bitmessage/entity/BitmessageAddress.java

@@ -57,6 +57,7 @@ public class BitmessageAddress implements Serializable {
 
     private String alias;
     private boolean subscribed;
+    private boolean chan;
 
     BitmessageAddress(long version, long stream, byte[] ripe) {
         try {
@@ -93,6 +94,27 @@ public class BitmessageAddress implements Serializable {
         this.pubkey = publicKey;
     }
 
+    public BitmessageAddress(String address, String passphrase) {
+        this(address);
+        this.privateKey = new PrivateKey(this, passphrase);
+        if (!Arrays.equals(ripe, privateKey.getPubkey().getRipe())) {
+            throw new IllegalArgumentException("Wrong address or passphrase");
+        }
+    }
+
+    public static BitmessageAddress chan(String address, String passphrase) {
+        BitmessageAddress result = new BitmessageAddress(address, passphrase);
+        result.chan = true;
+        return result;
+    }
+
+    public static BitmessageAddress chan(long stream, String passphrase) {
+        PrivateKey privateKey = new PrivateKey(Pubkey.LATEST_VERSION, stream, passphrase);
+        BitmessageAddress result = new BitmessageAddress(privateKey);
+        result.chan = true;
+        return result;
+    }
+
     public BitmessageAddress(PrivateKey privateKey) {
         this(privateKey.getPubkey());
         this.privateKey = privateKey;
@@ -221,4 +243,8 @@ public class BitmessageAddress implements Serializable {
     public void setSubscribed(boolean subscribed) {
         this.subscribed = subscribed;
     }
+
+    public boolean isChan() {
+        return chan;
+    }
 }

core/src/main/java/ch/dissem/bitmessage/entity/valueobject/PrivateKey.java

@@ -16,6 +16,7 @@
 
 package ch.dissem.bitmessage.entity.valueobject;
 
+import ch.dissem.bitmessage.entity.BitmessageAddress;
 import ch.dissem.bitmessage.entity.Streamable;
 import ch.dissem.bitmessage.entity.payload.Pubkey;
 import ch.dissem.bitmessage.exception.ApplicationException;
@@ -64,14 +65,32 @@ public class PrivateKey implements Streamable {
         this.pubkey = pubkey;
     }
 
-    public PrivateKey(long version, long stream, String passphrase, long nonceTrialsPerByte, long extraBytes, Pubkey.Feature... features) {
+    public PrivateKey(BitmessageAddress address, String passphrase) {
+        this(address.getVersion(), address.getStream(), passphrase);
+    }
+
+    public PrivateKey(long version, long stream, String passphrase) {
         try {
-            // FIXME: this is most definitely wrong
+            byte[] signingKey;
-            this.privateSigningKey = Bytes.truncate(security().sha512(passphrase.getBytes("UTF-8"), new byte[]{0}), 32);
+            int signingKeyNonce = 0;
-            this.privateEncryptionKey = Bytes.truncate(security().sha512(passphrase.getBytes("UTF-8"), new byte[]{1}), 32);
+            byte[] encryptionKey;
-            this.pubkey = security().createPubkey(version, stream, privateSigningKey, privateEncryptionKey,
+            int encryptionKeyNonce = 1;
-                    nonceTrialsPerByte, extraBytes, features);
+            byte[] passPhraseBytes = passphrase.getBytes("UTF-8");
-        } catch (UnsupportedEncodingException e) {
+            byte[] ripe;
+            do {
+                signingKey = Bytes.truncate(security().sha512(passPhraseBytes, Encode.varInt(signingKeyNonce)), 32);
+                encryptionKey = Bytes.truncate(security().sha512(passPhraseBytes, Encode.varInt(encryptionKeyNonce)), 32);
+                byte[] publicSigningKey = security().createPublicKey(signingKey);
+                byte[] publicEncryptionKey = security().createPublicKey(encryptionKey);
+                ripe = security().ripemd160(security().sha512(publicSigningKey, publicEncryptionKey));
+
+                signingKeyNonce += 2;
+                encryptionKeyNonce += 2;
+            } while (ripe[0] != 0);
+            this.privateSigningKey = signingKey;
+            this.privateEncryptionKey = encryptionKey;
+            this.pubkey = security().createPubkey(version, stream, privateSigningKey, privateEncryptionKey, 0, 0);
+        } catch (IOException e) {
             throw new ApplicationException(e);
         }
     }

core/src/main/java/ch/dissem/bitmessage/utils/Encode.java

@@ -41,6 +41,34 @@ public class Encode {
         varInt(value, stream, null);
     }
 
+    public static byte[] varInt(long value) throws IOException {
+        final byte[] result;
+        if (value < 0) {
+            // This is due to the fact that Java doesn't really support unsigned values.
+            // Please be aware that this might be an error due to a smaller negative value being cast to long.
+            // Normally, negative values shouldn't occur within the protocol, and I large enough longs
+            // to being recognized as negatives aren't realistic.
+            ByteBuffer buffer = ByteBuffer.allocate(9);
+            buffer.put((byte) 0xff);
+            result = buffer.putLong(value).array();
+        } else if (value < 0xfd) {
+            result = new byte[]{(byte) value};
+        } else if (value <= 0xffffL) {
+            ByteBuffer buffer = ByteBuffer.allocate(3);
+            buffer.put((byte) 0xfd);
+            result = buffer.putShort((short) value).array();
+        } else if (value <= 0xffffffffL) {
+            ByteBuffer buffer = ByteBuffer.allocate(5);
+            buffer.put((byte) 0xfe);
+            result = buffer.putInt((int) value).array();
+        } else {
+            ByteBuffer buffer = ByteBuffer.allocate(9);
+            buffer.put((byte) 0xff);
+            result = buffer.putLong(value).array();
+        }
+        return result;
+    }
+
     public static void varInt(long value, OutputStream stream, AccessCounter counter) throws IOException {
         if (value < 0) {
             // This is due to the fact that Java doesn't really support unsigned values.
@@ -81,7 +109,7 @@ public class Encode {
     }
 
     public static void int16(long value, OutputStream stream, AccessCounter counter) throws IOException {
-        stream.write(ByteBuffer.allocate(4).putInt((int) value).array(), 2, 2);
+        stream.write(ByteBuffer.allocate(2).putShort((short) value).array());
         inc(counter, 2);
     }
 

core/src/test/java/ch/dissem/bitmessage/BitmessageContextTest.java

@@ -39,7 +39,7 @@ import static ch.dissem.bitmessage.entity.payload.ObjectType.*;
 import static ch.dissem.bitmessage.utils.MessageMatchers.object;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.CoreMatchers.notNullValue;
-import static org.junit.Assert.assertThat;
+import static org.junit.Assert.*;
 import static org.mockito.Matchers.any;
 import static org.mockito.Mockito.*;
 
@@ -206,4 +206,21 @@ public class BitmessageContextTest {
                 .build();
         ctx.send(msg);
     }
+
+    @Test
+    public void ensureChanIsJoined() {
+        String chanAddress = "BM-2cW67GEKkHGonXKZLCzouLLxnLym3azS8r";
+        BitmessageAddress chan = ctx.joinChan("general", chanAddress);
+        assertNotNull(chan);
+        assertEquals(chan.getAddress(), chanAddress);
+        assertTrue(chan.isChan());
+    }
+
+    @Test
+    public void ensureChanIsCreated() {
+        BitmessageAddress chan = ctx.createChan("test");
+        assertNotNull(chan);
+        assertEquals(chan.getVersion(), Pubkey.LATEST_VERSION);
+        assertTrue(chan.isChan());
+    }
 }

core/src/test/java/ch/dissem/bitmessage/entity/BitmessageAddressTest.java

@@ -20,7 +20,10 @@ import ch.dissem.bitmessage.entity.payload.Pubkey;
 import ch.dissem.bitmessage.entity.payload.V4Pubkey;
 import ch.dissem.bitmessage.entity.valueobject.PrivateKey;
 import ch.dissem.bitmessage.exception.DecryptionFailedException;
-import ch.dissem.bitmessage.utils.*;
+import ch.dissem.bitmessage.utils.Base58;
+import ch.dissem.bitmessage.utils.Bytes;
+import ch.dissem.bitmessage.utils.Strings;
+import ch.dissem.bitmessage.utils.TestUtils;
 import org.junit.Test;
 
 import java.io.IOException;