From 225c78f3ab31d6e77457ca333fcb1f67182b11a9 Mon Sep 17 00:00:00 2001
From: Kris Nuttycombe <kris@nutty.land>
Date: Fri, 18 Feb 2022 19:00:00 -0600
Subject: [PATCH] Add Orchard components to unified spending keys

Co-authored-by: Jack Grigg <jack@z.cash>
---
 src/gtest/test_keys.cpp       | 28 ++++++++++++++++++++++++++++
 src/wallet/wallet.cpp         |  3 ++-
 src/zcash/address/unified.cpp |  5 ++++-
 src/zcash/address/unified.h   |  8 +++++++-
 4 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/src/gtest/test_keys.cpp b/src/gtest/test_keys.cpp
index d0578f990..6d68cdb57 100644
--- a/src/gtest/test_keys.cpp
+++ b/src/gtest/test_keys.cpp
@@ -195,6 +195,16 @@ TEST(Keys, DeriveUnifiedFullViewingKeys)
         if (test.size() == 1) continue; // comment
 
         try {
+            // [
+            //     t_key_bytes,
+            //     sapling_fvk_bytes,
+            //     orchard_fvk_bytes,
+            //     unknown_fvk_typecode,
+            //     unknown_fvk_bytes,
+            //     unified_fvk,
+            //     root_seed,
+            //     account,
+            // ],
             auto seed_hex = test[6].get_str();
             auto seed_data = ParseHex(seed_hex);
             RawHDSeed raw_seed(seed_data.begin(), seed_data.end());
@@ -244,6 +254,24 @@ TEST(Keys, DeriveUnifiedFullViewingKeys)
                 auto key = libzcash::SaplingDiversifiableFullViewingKey::Read(ss);
                 EXPECT_EQ(key, saplingKey);
             }
+            if (!test[2].isNull()) {
+                auto expectedHex = test[2].get_str();
+
+                // Ensure that the serialized Orchard fvk matches the test data.
+                auto orchardKey = ufvk.GetOrchardKey().value();
+                CDataStream ssEncode(SER_NETWORK, PROTOCOL_VERSION);
+                ssEncode << orchardKey;
+                EXPECT_EQ(ssEncode.size(), 96);
+                auto skeyHex = HexStr(ssEncode.begin(), ssEncode.end());
+                EXPECT_EQ(expectedHex, skeyHex);
+
+                // Ensure that parsing the test data derives the correct dfvk
+                auto data = ParseHex(expectedHex);
+                ASSERT_EQ(data.size(), 96);
+                CDataStream ss(data, SER_NETWORK, PROTOCOL_VERSION);
+                auto key = libzcash::OrchardFullViewingKey::Read(ss);
+                EXPECT_EQ(key, orchardKey);
+            }
             // Enable the following after Orchard keys are supported.
             //{
             //    auto fvk_data = ParseHex(test[5].get_str());
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 474c0eae8..f57bd8ae0 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -576,7 +576,8 @@ std::optional<libzcash::ZcashdUnifiedSpendingKey>
             throw std::runtime_error("CWallet::GenerateUnifiedSpendingKeyForAccount(): Failed to add Sapling change address to the wallet.");
         };
 
-        // TODO ORCHARD: Add Orchard component to the wallet
+        // Add Orchard spending key to the wallet
+        orchardWallet.AddSpendingKey(usk.value().GetOrchardKey());
 
         auto zufvk = ZcashdUnifiedFullViewingKey::FromUnifiedFullViewingKey(Params(), ufvk);
         if (!CCryptoKeyStore::AddUnifiedFullViewingKey(zufvk)) {
diff --git a/src/zcash/address/unified.cpp b/src/zcash/address/unified.cpp
index ca9a8f9b6..93dd1b34f 100644
--- a/src/zcash/address/unified.cpp
+++ b/src/zcash/address/unified.cpp
@@ -39,7 +39,9 @@ std::optional<ZcashdUnifiedSpendingKey> ZcashdUnifiedSpendingKey::ForAccount(
 
     auto saplingKey = SaplingExtendedSpendingKey::ForAccount(seed, bip44CoinType, accountId);
 
-    return ZcashdUnifiedSpendingKey(transparentKey.value(), saplingKey.first);
+    auto orchardKey = OrchardSpendingKey::ForAccount(seed, bip44CoinType, accountId);
+
+    return ZcashdUnifiedSpendingKey(transparentKey.value(), saplingKey.first, orchardKey);
 }
 
 UnifiedFullViewingKey ZcashdUnifiedSpendingKey::ToFullViewingKey() const {
@@ -47,6 +49,7 @@ UnifiedFullViewingKey ZcashdUnifiedSpendingKey::ToFullViewingKey() const {
 
     builder.AddTransparentKey(transparentKey.ToAccountPubKey());
     builder.AddSaplingKey(saplingKey.ToXFVK());
+    builder.AddOrchardKey(orchardKey.ToFullViewingKey());
 
     // This call to .value() is safe as ZcashdUnifiedSpendingKey values are always
     // constructed to contain all required components.
diff --git a/src/zcash/address/unified.h b/src/zcash/address/unified.h
index f388013bb..d76152239 100644
--- a/src/zcash/address/unified.h
+++ b/src/zcash/address/unified.h
@@ -248,10 +248,12 @@ class ZcashdUnifiedSpendingKey {
 private:
     transparent::AccountKey transparentKey;
     SaplingExtendedSpendingKey saplingKey;
+    OrchardSpendingKey orchardKey;
 
     ZcashdUnifiedSpendingKey(
             transparent::AccountKey tkey,
-            SaplingExtendedSpendingKey skey): transparentKey(tkey), saplingKey(skey) {}
+            SaplingExtendedSpendingKey skey,
+            OrchardSpendingKey okey): transparentKey(tkey), saplingKey(skey), orchardKey(okey) {}
 public:
     static std::optional<ZcashdUnifiedSpendingKey> ForAccount(
             const HDSeed& seed,
@@ -266,6 +268,10 @@ public:
         return saplingKey;
     }
 
+    const OrchardSpendingKey& GetOrchardKey() const {
+        return orchardKey;
+    }
+
     UnifiedFullViewingKey ToFullViewingKey() const;
 };