From 70c8c25e4bafce18cd7114080f3a54bae115f904 Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@z.cash>
Date: Fri, 3 Aug 2018 16:51:01 +0100
Subject: [PATCH] Store HDSeed in CBasicKeyStore

---
 src/gtest/test_keystore.cpp | 28 ++++++++++++++++++++++++++++
 src/keystore.cpp            | 24 ++++++++++++++++++++++++
 src/keystore.h              | 12 ++++++++++++
 3 files changed, 64 insertions(+)

diff --git a/src/gtest/test_keystore.cpp b/src/gtest/test_keystore.cpp
index 4b4baa1a4..4f2d0ea44 100644
--- a/src/gtest/test_keystore.cpp
+++ b/src/gtest/test_keystore.cpp
@@ -8,11 +8,39 @@
 #include "wallet/crypter.h"
 #endif
 #include "zcash/Address.hpp"
+#include "zcash/zip32.h"
 
 #include "json_test_vectors.h"
 
 #define MAKE_STRING(x) std::string((x), (x)+sizeof(x))
 
+TEST(keystore_tests, StoreAndRetrieveHDSeed) {
+    CBasicKeyStore keyStore;
+    HDSeed seedOut;
+
+    // When we haven't set a seed, we shouldn't get one
+    EXPECT_FALSE(keyStore.HaveHDSeed());
+    EXPECT_FALSE(keyStore.GetHDSeed(seedOut));
+
+    // Generate a random seed
+    auto seed = HDSeed::Random();
+
+    // We should be able to set and retrieve the seed
+    ASSERT_TRUE(keyStore.SetHDSeed(seed));
+    EXPECT_TRUE(keyStore.HaveHDSeed());
+    ASSERT_TRUE(keyStore.GetHDSeed(seedOut));
+    EXPECT_EQ(seed, seedOut);
+
+    // Generate another random seed
+    auto seed2 = HDSeed::Random();
+    EXPECT_NE(seed, seed2);
+
+    // We should be able to set and retrieve a different seed
+    ASSERT_TRUE(keyStore.SetHDSeed(seed2));
+    ASSERT_TRUE(keyStore.GetHDSeed(seedOut));
+    EXPECT_EQ(seed2, seedOut);
+}
+
 TEST(keystore_tests, sapling_keys) {
     // ["sk, ask, nsk, ovk, ak, nk, ivk, default_d, default_pk_d, note_v, note_r, note_cm, note_pos, note_nf"],
     UniValue sapling_keys = read_json(MAKE_STRING(json_tests::sapling_key_components));
diff --git a/src/keystore.cpp b/src/keystore.cpp
index 8e4310b38..efd084259 100644
--- a/src/keystore.cpp
+++ b/src/keystore.cpp
@@ -23,6 +23,30 @@ bool CKeyStore::AddKey(const CKey &key) {
     return AddKeyPubKey(key, key.GetPubKey());
 }
 
+bool CBasicKeyStore::SetHDSeed(const HDSeed& seed)
+{
+    LOCK(cs_SpendingKeyStore);
+    hdSeed = seed;
+    return true;
+}
+
+bool CBasicKeyStore::HaveHDSeed() const
+{
+    LOCK(cs_SpendingKeyStore);
+    return !hdSeed.IsNull();
+}
+
+bool CBasicKeyStore::GetHDSeed(HDSeed& seedOut) const
+{
+    LOCK(cs_SpendingKeyStore);
+    if (hdSeed.IsNull()) {
+        return false;
+    } else {
+        seedOut = hdSeed;
+        return true;
+    }
+}
+
 bool CBasicKeyStore::AddKeyPubKey(const CKey& key, const CPubKey &pubkey)
 {
     LOCK(cs_KeyStore);
diff --git a/src/keystore.h b/src/keystore.h
index 234f588b8..33ad8807e 100644
--- a/src/keystore.h
+++ b/src/keystore.h
@@ -13,6 +13,7 @@
 #include "sync.h"
 #include "zcash/Address.hpp"
 #include "zcash/NoteEncryption.hpp"
+#include "zcash/zip32.h"
 
 #include <boost/signals2/signal.hpp>
 #include <boost/variant.hpp>
@@ -27,6 +28,12 @@ protected:
 public:
     virtual ~CKeyStore() {}
 
+    //! Set the HD seed for this keystore
+    virtual bool SetHDSeed(const HDSeed& seed) =0;
+    virtual bool HaveHDSeed() const =0;
+    //! Get the HD seed for this keystore
+    virtual bool GetHDSeed(HDSeed& seedOut) const =0;
+
     //! Add a key to the store.
     virtual bool AddKeyPubKey(const CKey &key, const CPubKey &pubkey) =0;
     virtual bool AddKey(const CKey &key);
@@ -109,6 +116,7 @@ typedef std::map<libzcash::SaplingPaymentAddress, libzcash::SaplingIncomingViewi
 class CBasicKeyStore : public CKeyStore
 {
 protected:
+    HDSeed hdSeed;
     KeyMap mapKeys;
     ScriptMap mapScripts;
     WatchOnlySet setWatchOnly;
@@ -121,6 +129,10 @@ protected:
     SaplingIncomingViewingKeyMap mapSaplingIncomingViewingKeys;
 
 public:
+    bool SetHDSeed(const HDSeed& seed);
+    bool HaveHDSeed() const;
+    bool GetHDSeed(HDSeed& seedOut) const;
+
     bool AddKeyPubKey(const CKey& key, const CPubKey &pubkey);
     bool HaveKey(const CKeyID &address) const
     {