From a807994b9a96b5aab4833210b18d35370cd33f07 Mon Sep 17 00:00:00 2001
From: Mike Hearn <mike@plan99.net>
Date: Tue, 8 Apr 2014 14:40:43 +0200
Subject: [PATCH] Bump wallet version and add missing check (!) to detect
 wallets from the future. The absence/incompleteness of this feature had not
 been noticed before, and it means that old apps will fail to read HD wallets
 due to the new key enum value rather than a more sensible error (but there's
 still no chance of an old app accepting an HD wallet, so it should still be
 safe).

---
 .../google/bitcoin/store/UnreadableWalletException.java    | 4 ++++
 .../com/google/bitcoin/store/WalletProtobufSerializer.java | 3 +++
 .../google/bitcoin/store/WalletProtobufSerializerTest.java | 7 +++++++
 core/src/wallet.proto                                      | 2 +-
 4 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/com/google/bitcoin/store/UnreadableWalletException.java b/core/src/main/java/com/google/bitcoin/store/UnreadableWalletException.java
index 4c00bb2dc..0c9d31bcf 100644
--- a/core/src/main/java/com/google/bitcoin/store/UnreadableWalletException.java
+++ b/core/src/main/java/com/google/bitcoin/store/UnreadableWalletException.java
@@ -18,4 +18,8 @@ public class UnreadableWalletException extends Exception {
             super("Password incorrect");
         }
     }
+
+    public static class FutureVersion extends UnreadableWalletException {
+        public FutureVersion() { super("Unknown wallet version from the future."); }
+    }
 }
diff --git a/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java b/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java
index 98532bcdf..434bd2609 100644
--- a/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java
+++ b/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java
@@ -362,6 +362,9 @@ public class WalletProtobufSerializer {
      */
     public Wallet readWallet(NetworkParameters params, @Nullable WalletExtension[] extensions,
                              Protos.Wallet walletProto) throws UnreadableWalletException {
+        if (walletProto.getVersion() > 1)
+            throw new UnreadableWalletException.FutureVersion();
+
         // Read the scrypt parameters that specify how encryption and decryption is performed.
         KeyChainGroup chain;
         if (walletProto.hasEncryptionParameters()) {
diff --git a/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java b/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java
index f2a3a5a64..8905b3399 100644
--- a/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java
+++ b/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java
@@ -332,6 +332,13 @@ public class WalletProtobufSerializerTest {
         assertEquals(0, wallet5.getExtensions().size());
     }
 
+    @Test(expected = UnreadableWalletException.FutureVersion.class)
+    public void versions() throws Exception {
+        Protos.Wallet.Builder proto = Protos.Wallet.newBuilder(new WalletProtobufSerializer().walletToProto(myWallet));
+        proto.setVersion(2);
+        new WalletProtobufSerializer().readWallet(params, null, proto.build());
+    }
+
     private static class SomeFooExtension implements WalletExtension {
         private final byte[] data = new byte[]{1, 2, 3};
 
diff --git a/core/src/wallet.proto b/core/src/wallet.proto
index 2352dd759..2847f1f1f 100644
--- a/core/src/wallet.proto
+++ b/core/src/wallet.proto
@@ -322,7 +322,7 @@ message Wallet {
 
   // The version number of the wallet - used to detect wallets that were produced in the future
   // (i.e the wallet may contain some future format this protobuf/ code does not know about)
-  optional int32 version = 7;
+  optional int32 version = 7 [default = 1];
 
   // deprecated - do not recycle this numeric identifier
   // optional int32 minor_version = 8;