Merge pull request #47 from rnicoll/sun-x509-key

Add handling of X509Key wrapped EdDSA keys

Author: str4d

src/net/i2p/crypto/eddsa/EdDSAEngine.java

@@ -22,11 +22,14 @@
 import java.security.Signature;
 import java.security.SignatureException;
 import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.X509EncodedKeySpec;
 import java.util.Arrays;
 
 import net.i2p.crypto.eddsa.math.Curve;
 import net.i2p.crypto.eddsa.math.GroupElement;
 import net.i2p.crypto.eddsa.math.ScalarOps;
+import sun.security.x509.X509Key;
 
 /**
  * Signing and verification for EdDSA.
@@ -154,6 +157,16 @@ protected void engineInitVerify(PublicKey publicKey) throws InvalidKeyException
                 }
             } else if (!key.getParams().getHashAlgorithm().equals(digest.getAlgorithm()))
                 throw new InvalidKeyException("Key hash algorithm does not match chosen digest");
+        } else if (publicKey instanceof X509Key) {
+            // X509Certificate will sometimes contain an X509Key rather than the EdDSAPublicKey itself; the contained
+            // key is valid but needs to be instanced as an EdDSAPublicKey before it can be used.
+            EdDSAPublicKey parsedPublicKey;
+            try {
+                parsedPublicKey = new EdDSAPublicKey(new X509EncodedKeySpec(publicKey.getEncoded()));
+            } catch (InvalidKeySpecException ex) {
+                throw new InvalidKeyException("cannot handle X.509 EdDSA public key: " + publicKey.getAlgorithm());
+            }
+            engineInitVerify(parsedPublicKey);
         } else {
             throw new InvalidKeyException("cannot identify EdDSA public key: " + publicKey.getClass());
         }

test/net/i2p/crypto/eddsa/EdDSAEngineTest.java

@@ -21,6 +21,7 @@
 import java.security.PublicKey;
 import java.security.Signature;
 import java.security.SignatureException;
+import java.security.cert.X509Certificate;
 
 import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable;
 import net.i2p.crypto.eddsa.spec.EdDSAParameterSpec;
@@ -30,6 +31,8 @@
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
+import sun.security.util.DerValue;
+import sun.security.x509.X509Key;
 
 /**
  * @author str4d
@@ -213,4 +216,21 @@ public void testVerifyOneShot() throws Exception {
 
         assertThat("verifyOneShot() failed", sgr.verifyOneShot(TEST_MSG, TEST_MSG_SIG), is(true));
     }
+
+    @Test
+    public void testVerifyX509PublicKeyInfo() throws Exception {
+        EdDSAParameterSpec spec = EdDSANamedCurveTable.getByName("Ed25519");
+        Signature sgr = new EdDSAEngine(MessageDigest.getInstance(spec.getHashAlgorithm()));
+        for (Ed25519TestVectors.TestTuple testCase : Ed25519TestVectors.testCases) {
+            EdDSAPublicKeySpec pubKey = new EdDSAPublicKeySpec(testCase.pk, spec);
+            PublicKey vKey = new EdDSAPublicKey(pubKey);
+            PublicKey x509Key = X509Key.parse(new DerValue(vKey.getEncoded()));
+            sgr.initVerify(x509Key);
+
+            sgr.update(testCase.message);
+
+            assertThat("Test case " + testCase.caseNum + " failed",
+                    sgr.verify(testCase.sig), is(true));
+        }
+    }
 }