Crypto: Fix privkey encoding to follow PKCS8,

ignore example in josefsson draft,
required for keytool to work.
Fix pubkey decode typo.
(ticket #1723)

core/java/src/net/i2p/crypto/KeyStoreUtil.java

@@ -479,6 +479,7 @@ public class KeyStoreUtil {
         List<String> a = new ArrayList<String>(32);
         a.add(keytool);
         a.add("-genkey");    // -genkeypair preferred in newer keytools, but this works with more
+        //a.add("-v");         // verbose, gives you a stack trace on exception
         a.add("-storetype"); a.add(KeyStore.getDefaultType());
         a.add("-keystore");  a.add(ks.getAbsolutePath());
         a.add("-storepass"); a.add(ksPW);
@@ -765,6 +766,7 @@ public class KeyStoreUtil {
      *          KeyStoreUtil import file.ks file.key alias keypw (imxports private key from file to keystore)
      *          KeyStoreUtil export file.ks alias keypw (exports private key from keystore)
      *          KeyStoreUtil keygen file.ks alias keypw (create keypair in keystore)
+     *          KeyStoreUtil keygen2 file.ks alias keypw (create keypair using I2PProvider)
      */
 /****
     public static void main(String[] args) {
@@ -781,6 +783,10 @@ public class KeyStoreUtil {
                 testKeygen(args);
                 return;
             }
+            if (args.length > 0 && "keygen2".equals(args[0])) {
+                testKeygen2(args);
+                return;
+            }
             File ksf = (args.length > 0) ? new File(args[0]) : null;
             if (ksf != null && !ksf.exists()) {
                 createKeyStore(ksf, DEFAULT_KEYSTORE_PASSWORD);
@@ -835,5 +841,26 @@ public class KeyStoreUtil {
                                 DEFAULT_KEY_VALID_DAYS, "EdDSA", 256, pw);
         System.out.println("genkey ok? " + ok);
     }
+
+    private static void testKeygen2(String[] args) throws Exception {
+        // keygen test using the I2PProvider
+        SigType type = SigType.EdDSA_SHA512_Ed25519;
+        java.security.KeyPairGenerator kpg = java.security.KeyPairGenerator.getInstance(type.getBaseAlgorithm().getName());
+        kpg.initialize(type.getParams());
+        java.security.KeyPair kp = kpg.generateKeyPair();
+        java.security.PublicKey jpub = kp.getPublic();
+        java.security.PrivateKey jpriv = kp.getPrivate();
+
+        System.out.println("Encoded private key:");
+        System.out.println(net.i2p.util.HexDump.dump(jpriv.getEncoded()));
+        System.out.println("Encoded public key:");
+        System.out.println(net.i2p.util.HexDump.dump(jpub.getEncoded()));
+
+        java.security.Signature jsig = java.security.Signature.getInstance("SHA512withEdDSA");
+        jsig.initSign(jpriv);
+        jsig.update(new byte[111]);
+        net.i2p.data.Signature sig = SigUtil.fromJavaSig(jsig.sign(), type);
+        System.out.println("Signature test: " + sig);
+    }
 ****/
 }

core/java/src/net/i2p/crypto/eddsa/EdDSAPrivateKey.java

@@ -53,7 +53,7 @@ public class EdDSAPrivateKey implements EdDSAKey, PrivateKey {
     /**
      *  This follows the spec at
      *  https://tools.ietf.org/html/draft-josefsson-pkix-eddsa-04
-     *  NOT the docs from
+     *  AND the docs from
      *  java.security.spec.PKCS8EncodedKeySpec
      *  quote:
      *<pre>
@@ -77,39 +77,43 @@ public class EdDSAPrivateKey implements EdDSAKey, PrivateKey {
      *  }
      *</pre>
      *
-     *  @return 39 bytes for Ed25519, null for other curves
+     *  Note that the private key encoding is not fully specified in the Josefsson draft,
+     *  and the example is wrong, as it's lacking Version and AlgorithmIdentifier.
+     *  But sun.security.pkcs.PKCS8Key expects them so we must include them for keytool to work.
+     *
+     *  @return 49 bytes for Ed25519, null for other curves
      *  @since implemented in 0.9.25
      */
     public byte[] getEncoded() {
         // TODO no equals() implemented in spec, but it's essentially a singleton
         if (!edDsaSpec.equals(EdDSANamedCurveTable.getByName(EdDSANamedCurveTable.CURVE_ED25519_SHA512)))
             return null;
-        int totlen = 7 + seed.length;
+        int totlen = 17 + seed.length;
         byte[] rv = new byte[totlen];
         int idx = 0;
         // sequence
         rv[idx++] = 0x30;
-        rv[idx++] = (byte) (5 + seed.length);
+        rv[idx++] = (byte) (15 + seed.length);
 
         // version
         // not in the Josefsson example
-        //rv[idx++] = 0x02;
+        rv[idx++] = 0x02;
-        //rv[idx++] = 1;
+        rv[idx++] = 1;
-        //rv[idx++] = 0;
+        rv[idx++] = 0;
 
         // Algorithm Identifier
         // sequence
         // not in the Josefsson example
-        //rv[idx++] = 0x30;
+        rv[idx++] = 0x30;
-        //rv[idx++] = (byte) (10 + seed.length);
+        rv[idx++] = 8;
         // OID 1.3.101.100
         // https://msdn.microsoft.com/en-us/library/windows/desktop/bb540809%28v=vs.85%29.aspx
         // not in the Josefsson example
-        //rv[idx++] = 0x06;
+        rv[idx++] = 0x06;
-        //rv[idx++] = 3;
+        rv[idx++] = 3;
-        //rv[idx++] = (1 * 40) + 3;
+        rv[idx++] = (1 * 40) + 3;
-        //rv[idx++] = 101;
+        rv[idx++] = 101;
-        //rv[idx++] = 100;
+        rv[idx++] = 100;
         // params
         rv[idx++] = 0x0a;
         rv[idx++] = 1;
@@ -132,7 +136,17 @@ public class EdDSAPrivateKey implements EdDSAKey, PrivateKey {
         try {
             int idx = 0;
             if (d[idx++] != 0x30 ||
-                d[idx++] != 37 ||
+                d[idx++] != 47 ||
+                d[idx++] != 0x02 ||
+                d[idx++] != 1 ||
+                d[idx++] != 0 ||
+                d[idx++] != 0x30 ||
+                d[idx++] != 8 ||
+                d[idx++] != 0x06 ||
+                d[idx++] != 3 ||
+                d[idx++] != (1 * 40) + 3 ||
+                d[idx++] != 101 ||
+                d[idx++] != 100 ||
                 d[idx++] != 0x0a ||
                 d[idx++] != 1 ||
                 d[idx++] != 1 ||

core/java/src/net/i2p/crypto/eddsa/EdDSAPublicKey.java

@@ -118,7 +118,7 @@ public class EdDSAPublicKey implements EdDSAKey, PublicKey {
                 d[idx++] != 0x30 ||
                 d[idx++] != 8 ||
                 d[idx++] != 0x06 ||
-                d[idx++] != 1 ||
+                d[idx++] != 3 ||
                 d[idx++] != (1 * 40) + 3 ||
                 d[idx++] != 101 ||
                 d[idx++] != 100 ||