Merge #11022: Basic keypool topup

d34957e [wallet] [tests] Add keypool topup functional test (Jonas Schnelli)
095142d [wallet] keypool mark-used and topup (John Newbery)
c25d90f [wallet] Add HasUnusedKeys() helper (John Newbery)
f2123e3 [wallet] Cache keyid -> keypool id mappings (John Newbery)
83f1ec3 [wallet] Don't hold cs_LastBlockFile while calling setBestChain (John Newbery)
2376bfc [wallet] [moveonly] Move LoadKeyPool to cpp (Matt Corallo)
cab8557 [wallet] [moveonly] Move CAffectedKeysVisitor (Jonas Schnelli)

Pull request description:

  This PR contains the first part of #10882 :

  - if a key from the keypool is used, mark all keys up to that key as used, and then try to top up the keypool
  - top up the keypool on startup

  Notably, it does not stop the node or prevent the best block from advancing if the keypool drops below a threshold (which means that transactions may be missed and funds lost if restoring from an old HD wallet backup).

Tree-SHA512: ac681fefeaf7ec2aab2fa1da93d12273ea80bd05eb48d7b3b551ea6e5d975dd97ba7de52b7fba52993823280ac4079cc36cf78a27dac708107ebf8fb6326142b

1 files changed, 11 insertions, 19 deletions

diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 3a02d1305d..0e26d6cc6a 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -705,6 +705,7 @@ private:
     std::set<int64_t> setInternalKeyPool;
     std::set<int64_t> setExternalKeyPool;
     int64_t m_max_keypool_index;
+    std::map<CKeyID, int64_t> m_pool_key_to_index;
 
     int64_t nTimeFirstKey;
 
@@ -747,22 +748,7 @@ public:
         }
     }
 
-    void LoadKeyPool(int64_t nIndex, const CKeyPool &keypool)
-    {
-        if (keypool.fInternal) {
-            setInternalKeyPool.insert(nIndex);
-        } else {
-            setExternalKeyPool.insert(nIndex);
-        }
-        m_max_keypool_index = std::max(m_max_keypool_index, nIndex);
-
-        // If no metadata exists yet, create a default with the pool key's
-        // creation time. Note that this may be overwritten by actually
-        // stored metadata for that key later, which is fine.
-        CKeyID keyid = keypool.vchPubKey.GetID();
-        if (mapKeyMetadata.count(keyid) == 0)
-            mapKeyMetadata[keyid] = CKeyMetadata(keypool.nTime);
-    }
+    void LoadKeyPool(int64_t nIndex, const CKeyPool &keypool);
 
     // Map from Key ID (for regular keys) or Script ID (for watch-only keys) to
     // key metadata.
@@ -828,7 +814,7 @@ public:
     const CWalletTx* GetWalletTx(const uint256& hash) const;
 
     //! check whether we are allowed to upgrade (or already support) to the named feature
-    bool CanSupportFeature(enum WalletFeature wf) { AssertLockHeld(cs_wallet); return nWalletMaxVersion >= wf; }
+    bool CanSupportFeature(enum WalletFeature wf) const { AssertLockHeld(cs_wallet); return nWalletMaxVersion >= wf; }
 
     /**
      * populate vCoins with vector of available COutputs.
@@ -990,10 +976,16 @@ public:
     bool TopUpKeyPool(unsigned int kpSize = 0);
     void ReserveKeyFromKeyPool(int64_t& nIndex, CKeyPool& keypool, bool fRequestedInternal);
     void KeepKey(int64_t nIndex);
-    void ReturnKey(int64_t nIndex, bool fInternal);
+    void ReturnKey(int64_t nIndex, bool fInternal, const CPubKey& pubkey);
     bool GetKeyFromPool(CPubKey &key, bool internal = false);
     int64_t GetOldestKeyPoolTime();
-    void GetAllReserveKeys(std::set<CKeyID>& setAddress) const;
+    /**
+     * Marks all keys in the keypool up to and including reserve_key as used.
+     */
+    void MarkReserveKeysAsUsed(int64_t keypool_id);
+    const std::map<CKeyID, int64_t>& GetAllReserveKeys() const { return m_pool_key_to_index; }
+    /** Does the wallet have at least min_keys in the keypool? */
+    bool HasUnusedKeys(int min_keys) const;
 
     std::set< std::set<CTxDestination> > GetAddressGroupings();
     std::map<CTxDestination, CAmount> GetAddressBalances();