Signature check works

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

@@ -41,7 +41,7 @@ public class BitmessageAddress {
     /**
      * Used for V4 address encryption. It's easier to just create it regardless of address version.
      */
-    private final byte[] privateEncryptionKey;
+    private final byte[] pubkeyDecryptionKey;
 
     private String address;
 
@@ -62,7 +62,7 @@ public class BitmessageAddress {
             // for the tag, the checksum has to be created with 0x00 padding
             byte[] checksum = Security.doubleSha512(os.toByteArray(), ripe);
             this.tag = Arrays.copyOfRange(checksum, 32, 64);
-            this.privateEncryptionKey = Arrays.copyOfRange(checksum, 0, 32);
+            this.pubkeyDecryptionKey = Arrays.copyOfRange(checksum, 0, 32);
             // but for the address and its checksum they need to be stripped
             int offset = Bytes.numberOfLeadingZeros(ripe);
             os.write(ripe, offset, ripe.length - offset);
@@ -103,7 +103,7 @@ public class BitmessageAddress {
             }
             checksum = Security.doubleSha512(Arrays.copyOfRange(bytes, 0, counter.length()), ripe);
             this.tag = Arrays.copyOfRange(checksum, 32, 64);
-            this.privateEncryptionKey = Arrays.copyOfRange(checksum, 0, 32);
+            this.pubkeyDecryptionKey = Arrays.copyOfRange(checksum, 0, 32);
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
@@ -135,20 +135,18 @@ public class BitmessageAddress {
 
     public void setPubkey(Pubkey pubkey) {
         if (pubkey instanceof V4Pubkey) {
-            try {
+            if (!Arrays.equals(tag, ((V4Pubkey) pubkey).getTag()))
-                V4Pubkey v4 = (V4Pubkey) pubkey;
-                if (!Arrays.equals(tag, v4.getTag()))
                 throw new IllegalArgumentException("Pubkey has incompatible tag");
-                v4.decrypt(privateEncryptionKey);
-            } catch (IOException e) {
-                throw new RuntimeException(e);
-            }
         }
         if (!Arrays.equals(ripe, pubkey.getRipe()))
             throw new IllegalArgumentException("Pubkey has incompatible ripe");
         this.pubkey = pubkey;
     }
 
+    public byte[] getPubkeyDecryptionKey() {
+        return pubkeyDecryptionKey;
+    }
+
     public PrivateKey getPrivateKey() {
         return privateKey;
     }

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

@@ -25,4 +25,6 @@ public interface Encrypted {
     void encrypt(byte[] publicKey) throws IOException;
 
     void decrypt(byte[] privateKey) throws IOException;
+
+    boolean isDecrypted();
 }

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

@@ -90,6 +90,10 @@ public class ObjectMessage implements MessagePayload {
         return new InventoryVector(Bytes.truncate(Security.doubleSha512(nonce, getPayloadBytesWithoutNonce()), 32));
     }
 
+    private boolean isEncrypted() {
+        return payload instanceof Encrypted && !((Encrypted) payload).isDecrypted();
+    }
+
     public boolean isSigned() {
         return payload.isSigned();
     }
@@ -103,10 +107,23 @@ public class ObjectMessage implements MessagePayload {
 
     public void sign(PrivateKey key) {
         // TODO
+//        Security.
     }
 
-    public boolean isSignatureValid() throws IOException {
+    public void decrypt(PrivateKey key) throws IOException {
-        Pubkey pubkey = null; // TODO
+        if (payload instanceof Encrypted){
+            ((Encrypted) payload).decrypt(key.getPrivateEncryptionKey());
+        }
+    }
+
+    public void decrypt(byte[] privateEncryptionKey) throws IOException {
+        if (payload instanceof Encrypted){
+            ((Encrypted) payload).decrypt(privateEncryptionKey);
+        }
+    }
+
+    public boolean isSignatureValid(Pubkey pubkey) throws IOException {
+        if (isEncrypted()) throw new IllegalStateException("Payload must be decrypted first");
         return Security.isSignatureValid(getBytesToSign(), payload.getSignature(), pubkey);
     }
 

domain/src/main/java/ch/dissem/bitmessage/entity/payload/V4Pubkey.java

@@ -65,12 +65,23 @@ public class V4Pubkey extends Pubkey implements Encrypted {
         decrypted = V3Pubkey.read(encrypted.decrypt(privateKey), stream);
     }
 
+    @Override
+    public boolean isDecrypted() {
+        return decrypted != null;
+    }
+
     @Override
     public void write(OutputStream stream) throws IOException {
         stream.write(tag);
         encrypted.write(stream);
     }
 
+    @Override
+    public void writeBytesToSign(OutputStream out) throws IOException {
+        out.write(tag);
+        decrypted.writeBytesToSign(out);
+    }
+
     @Override
     public long getVersion() {
         return 4;

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

@@ -22,8 +22,14 @@ import ch.dissem.bitmessage.factory.Factory;
 import ch.dissem.bitmessage.ports.ProofOfWorkEngine;
 import org.bouncycastle.asn1.x9.X9ECParameters;
 import org.bouncycastle.crypto.ec.CustomNamedCurves;
+import org.bouncycastle.jce.ECNamedCurveTable;
+import org.bouncycastle.jce.ECPointUtil;
 import org.bouncycastle.jce.provider.BouncyCastleProvider;
+import org.bouncycastle.jce.spec.ECNamedCurveSpec;
+import org.bouncycastle.jce.spec.ECParameterSpec;
+import org.bouncycastle.jce.spec.ECPublicKeySpec;
 import org.bouncycastle.math.ec.ECPoint;
+import org.bouncycastle.util.encoders.Hex;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -31,9 +37,8 @@ import javax.crypto.Mac;
 import javax.crypto.spec.SecretKeySpec;
 import java.io.IOException;
 import java.math.BigInteger;
-import java.security.GeneralSecurityException;
+import java.security.*;
-import java.security.MessageDigest;
+import java.security.spec.KeySpec;
-import java.security.SecureRandom;
 import java.util.Arrays;
 
 /**
@@ -181,18 +186,24 @@ public class Security {
 
     public static boolean isSignatureValid(byte[] bytesToSign, byte[] signature, Pubkey pubkey) {
         ECPoint W = keyToPoint(pubkey.getSigningKey());
-//        try {
+        try {
-//            ECParameterSpec param = null;
+            ECParameterSpec spec = new ECParameterSpec(
-//            KeySpec keySpec = new ECPublicKeySpec(W, param);
+                    EC_CURVE_PARAMETERS.getCurve(),
-//            PublicKey publicKey = KeyFactory.getInstance("ECDSA", "BC").generatePublic(keySpec);
+                    EC_CURVE_PARAMETERS.getG(),
-//
+                    EC_CURVE_PARAMETERS.getN(),
-//            Signature sig = Signature.getInstance("ECDSA", "BC");
+                    EC_CURVE_PARAMETERS.getH(),
-//            sig.initVerify(publicKey);
+                    EC_CURVE_PARAMETERS.getSeed()
-//            sig.update(bytesToSign);
+            );
-//            return sig.verify(signature);
+
-//        } catch (Exception e) {
+            KeySpec keySpec = new ECPublicKeySpec(W, spec);
-//            throw new RuntimeException(e);
+            PublicKey publicKey = KeyFactory.getInstance("ECDSA", "BC").generatePublic(keySpec);
-//        }
+
-        return false; // TODO
+            Signature sig = Signature.getInstance("ECDSA", "BC");
+            sig.initVerify(publicKey);
+            sig.update(bytesToSign);
+            return sig.verify(signature);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
     }
 }

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

@@ -73,6 +73,7 @@ public class BitmessageAddressTest {
 
         ObjectMessage object = TestUtils.loadObjectMessage(3, "V3Pubkey.payload");
         Pubkey pubkey = (Pubkey) object.getPayload();
+        assertTrue(object.isSignatureValid(pubkey));
         address.setPubkey(pubkey);
 
         assertArrayEquals(Bytes.fromHex("007402be6e76c3cb87caa946d0c003a3d4d8e1d5"), pubkey.getRipe());
@@ -80,10 +81,11 @@ public class BitmessageAddressTest {
 
     @Test
     public void testV4PubkeyImport() throws IOException {
-        // TODO
-        ObjectMessage object = TestUtils.loadObjectMessage(4, "V4Pubkey.payload");
-        V4Pubkey pubkey = (V4Pubkey) object.getPayload();
         BitmessageAddress address = new BitmessageAddress("BM-2cXxfcSetKnbHJX2Y85rSkaVpsdNUZ5q9h");
+        ObjectMessage object = TestUtils.loadObjectMessage(4, "V4Pubkey.payload");
+        object.decrypt(address.getPubkeyDecryptionKey());
+        V4Pubkey pubkey = (V4Pubkey) object.getPayload();
+        assertTrue(object.isSignatureValid(pubkey));
         address.setPubkey(pubkey);
     }