Port from 0.13: Create a new HD seed after encrypting the wallet

Forward-ports two commits from 0.13:
- [0.13] Create a new HD seed after encrypting the wallet
- [Wallet] Add CKeyMetadata record for HDMasterKey(s), factor out HD key generation

Github-Pull: #8389
Rebased-From: f142c11ac634df487cc4bc65a5f1c9a3e3563dd9 de45c065f0648c4c41b57cb492420ceeed29dd11

1 files changed, 42 insertions, 10 deletions

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 5908dfeac..e5ee5063a 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -626,6 +626,15 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
 
         Lock();
         Unlock(strWalletPassphrase);
+
+        // if we are using HD, replace the HD master key (seed) with a new one
+        if (!hdChain.masterKeyID.IsNull()) {
+            CKey key;
+            CPubKey masterPubKey = GenerateNewHDMasterKey();
+            if (!SetHDMasterKey(masterPubKey))
+                return false;
+        }
+
         NewKeyPool();
         Lock();
 
@@ -1166,20 +1175,43 @@ CAmount CWallet::GetChange(const CTransaction& tx) const
     return nChange;
 }
 
-bool CWallet::SetHDMasterKey(const CKey& key)
+CPubKey CWallet::GenerateNewHDMasterKey()
+{
+    CKey key;
+    key.MakeNewKey(true);
+
+    int64_t nCreationTime = GetTime();
+    CKeyMetadata metadata(nCreationTime);
+
+    // calculate the pubkey
+    CPubKey pubkey = key.GetPubKey();
+    assert(key.VerifyPubKey(pubkey));
+
+    // set the hd keypath to "m" -> Master, refers the masterkeyid to itself
+    metadata.hdKeypath     = "m";
+    metadata.hdMasterKeyID = pubkey.GetID();
+
+    {
+        LOCK(cs_wallet);
+
+        // mem store the metadata
+        mapKeyMetadata[pubkey.GetID()] = metadata;
+
+        // write the key&metadata to the database
+        if (!AddKeyPubKey(key, pubkey))
+            throw std::runtime_error("CWallet::GenerateNewKey(): AddKey failed");
+    }
+
+    return pubkey;
+}
+
+bool CWallet::SetHDMasterKey(const CPubKey& pubkey)
 {
     LOCK(cs_wallet);
 
     // ensure this wallet.dat can only be opened by clients supporting HD
     SetMinVersion(FEATURE_HD);
 
-    // store the key as normal "key"/"ckey" object
-    // in the database
-    // key metadata is not required
-    CPubKey pubkey = key.GetPubKey();
-    if (!AddKeyPubKey(key, pubkey))
-        throw std::runtime_error("CWallet::GenerateNewKey(): AddKey failed");
-
     // store the keyid (hash160) together with
     // the child index counter in the database
     // as a hdchain object
@@ -3299,8 +3331,8 @@ bool CWallet::InitLoadWallet()
         if (GetBoolArg("-usehd", DEFAULT_USE_HD_WALLET) && walletInstance->hdChain.masterKeyID.IsNull()) {
             // generate a new master key
             CKey key;
-            key.MakeNewKey(true);
-            if (!walletInstance->SetHDMasterKey(key))
+            CPubKey masterPubKey = walletInstance->GenerateNewHDMasterKey();
+            if (!walletInstance->SetHDMasterKey(masterPubKey))
                 throw std::runtime_error("CWallet::GenerateNewKey(): Storing master key failed");
         }
         CPubKey newDefaultKey;