Issues/293

build.gradle

@@ -14,7 +14,7 @@ apply plugin: 'java'
 
 group = 'network.casper'
 // Version number update for release
-version='2.5.7'
+version='2.5.8'
 sourceCompatibility = 1.8
 targetCompatibility = 1.8
 

src/main/java/com/syntifi/crypto/key/Secp256k1PublicKey.java

@@ -4,13 +4,14 @@
 import lombok.EqualsAndHashCode;
 import lombok.NoArgsConstructor;
 import org.bouncycastle.asn1.*;
+import org.web3j.crypto.ECDSASignature;
 import org.web3j.crypto.Hash;
 import org.web3j.crypto.Sign;
-import org.web3j.crypto.Sign.SignatureData;
 
-import java.io.*;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
 import java.math.BigInteger;
-import java.security.GeneralSecurityException;
 import java.util.Arrays;
 
 /**
@@ -62,21 +63,52 @@ public void writePublicKey(final Writer writer) throws IOException {
         PemFileHelper.writePemFile(writer, derKey.getEncoded(), ASN1Identifiers.PUBLIC_KEY_DER_HEADER);
     }
 
+    /**
+     * Iterates possible signature combinations and possible recovery id's
+     * Casper does not use signature.v so we have to iterate v
+     * We don't know v so we have to iterate the possible recover id's
+     * Converts to short public key for comparison
+     *
+     * @param message   the signed message
+     * @param signature the signature to check against
+     * @return true|false public key found
+     */
     @Override
-    public Boolean verify(final byte[] message, final byte[] signature) throws GeneralSecurityException {
-        //TODO: Double check the issue the getV(), for now we are trying with both (27 and 28)
-        final SignatureData signatureData1 = new SignatureData(
-                (byte) 27,
-                Arrays.copyOfRange(signature, 0, 32),
-                Arrays.copyOfRange(signature, 32, 64));
-        final BigInteger derivedKey1 = Sign.signedMessageHashToKey(Hash.sha256(message), signatureData1);
-        final SignatureData signatureData2 = new SignatureData(
-                (byte) 28,
-                Arrays.copyOfRange(signature, 0, 32),
-                Arrays.copyOfRange(signature, 32, 64));
-        final BigInteger derivedKey2 = Sign.signedMessageHashToKey(Hash.sha256(message), signatureData2);
-        return Arrays.equals(Secp256k1PublicKey.getShortKey(derivedKey1.toByteArray()), getKey()) ||
-                Arrays.equals(Secp256k1PublicKey.getShortKey(derivedKey2.toByteArray()), getKey());
+    public Boolean verify(byte[] message, byte[] signature) {
+
+        //We need the Public key's short key
+        byte[] keyToFind = (getKey().length > 33) ? getShortKey(getKey()) : getKey();
+
+        //Looping possible v's of the signature
+        for (int i = 27; i <= 34; i++) {
+
+            final Sign.SignatureData signatureData =
+                    new Sign.SignatureData(
+                            (byte) (i),
+                            Arrays.copyOfRange(signature, 0, 32),
+                            Arrays.copyOfRange(signature, 32, 64));
+
+            //iterate the recovery id's
+            for (int j = 0; j < 4; j++) {
+
+                final ECDSASignature ecdsaSignature = new ECDSASignature(new BigInteger(1, signatureData.getR()),
+                        new BigInteger(1, signatureData.getS()));
+                final BigInteger recoveredKey = Sign.recoverFromSignature((byte) j, ecdsaSignature, Hash.sha256(message));
+
+                if (recoveredKey != null) {
+
+                    final byte[] keyFromSignature = getShortKey(recoveredKey.toByteArray());
+
+                    if (Arrays.equals(keyFromSignature, keyToFind)) {
+                        return true;
+                    }
+                }
+            }
+
+        }
+
+        return false;
+
     }
 
     /**

src/test/java/com/syntifi/crypto/key/Secp256k1PublicKeyTests.java

@@ -8,7 +8,6 @@
 import java.io.File;
 import java.io.IOException;
 import java.net.URISyntaxException;
-import java.security.GeneralSecurityException;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Date;
@@ -50,7 +49,7 @@ void writePublicKey_should_equal_source_file() throws URISyntaxException, IOExce
     }
 
     @Test
-    void verify_should_be_ok() throws URISyntaxException, IOException, GeneralSecurityException {
+    void verify_should_be_ok() throws URISyntaxException, IOException {
         String hexSignature = "ea5b38fd0db5fb3d871c47fde1fa4c4db75d1a9e1c0ac54d826e178ee0e63707176b4e63b4f838bd031f007fffd6a4f71d920a10c48ea53dd1573fa2b58a829e";
 
         Secp256k1PublicKey pubKey = new Secp256k1PublicKey();
@@ -60,4 +59,91 @@ void verify_should_be_ok() throws URISyntaxException, IOException, GeneralSecuri
 
         assertTrue(pubKey.verify("Test message".getBytes(), Hex.decode(hexSignature)));
     }
-}
+
+    @Test
+    void signAndRecoverPublicKey_1() throws URISyntaxException, IOException {
+
+        //Get the private key
+        Secp256k1PrivateKey privKey = new Secp256k1PrivateKey();
+        String filePath = getResourcesKeyPath("secp256k1/secret_key.pem");
+        privKey.readPrivateKey(filePath);
+
+        //Derive the public key
+        Secp256k1PublicKey publicKey = (Secp256k1PublicKey) privKey.derivePublicKey();
+
+        String message = "bc81ca4de9b3a991a6514eddf0e994e0035c7ba58f333c4d7ba5dd18b4c9c547";
+
+        //Generate the signature
+        byte[] signature = privKey.sign(message.getBytes());
+
+        //Test
+        assert publicKey.verify(message.getBytes(), signature);
+
+    }
+
+    @Test
+    void signAndRecoverPublicKey_2() throws URISyntaxException, IOException {
+
+        //Get the private key
+        Secp256k1PrivateKey privKey = new Secp256k1PrivateKey();
+
+        String filePath = getResourcesKeyPath("secp256k1/secret_key.pem");
+        privKey.readPrivateKey(filePath);
+
+        //Derive the public key
+        Secp256k1PublicKey publicKey = (Secp256k1PublicKey) privKey.derivePublicKey();
+
+        String message = "1df13c9aaa8217657b7e5ec2442594735eeb4ca7e764877b3d2b593c3909d15f";
+
+        //Generate the signature
+        byte[] signature = privKey.sign(message.getBytes());
+
+        //Test
+        assert publicKey.verify(message.getBytes(), signature);
+
+    }
+
+    @Test
+    void signAndRecoverPublicKey_3() throws URISyntaxException, IOException {
+
+        //Get the private key
+        Secp256k1PrivateKey privKey = new Secp256k1PrivateKey();
+        String filePath = getResourcesKeyPath("secp256k1/secret_key.pem");
+        privKey.readPrivateKey(filePath);
+
+        //Derive the public key
+        Secp256k1PublicKey publicKey = (Secp256k1PublicKey) privKey.derivePublicKey();
+
+        String message = "Test message";
+
+        //Generate the signature
+        byte[] signature = privKey.sign(message.getBytes());
+
+        //Test
+        assert publicKey.verify(message.getBytes(), signature);
+
+    }
+
+    @Test
+    void signAndRecoverPublicKey_4() throws URISyntaxException, IOException {
+
+        //Get the private key
+        Secp256k1PrivateKey privKey = new Secp256k1PrivateKey();
+        String filePath = getResourcesKeyPath("secp256k1/secret_key.pem");
+        privKey.readPrivateKey(filePath);
+
+        //Derive the public key
+        Secp256k1PublicKey publicKey = (Secp256k1PublicKey) privKey.derivePublicKey();
+
+        String message = "Test message";
+
+        //Generate the signature
+        byte[] signature = privKey.sign(message.getBytes());
+
+        //Test
+        assert publicKey.verify(message.getBytes(), signature);
+        assert !publicKey.verify("Not test message".getBytes(), signature);
+
+    }
+
+}