Wallet/RPC: sweepprivkeys method to scan UTXO set and send to local wallet

src/coins.cpp

@@ -9,6 +9,8 @@
 
 #include <assert.h>
 
+#include <stdexcept>
+
 /**
  * calculate number of bytes for the bitmask, and its number of non-zero bytes
  * each bit in the bitmask represents the availability of one output, but the
@@ -47,6 +49,36 @@ uint256 CCoinsView::GetBestBlock() const { return uint256(); }
 bool CCoinsView::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) { return false; }
 CCoinsViewCursor *CCoinsView::Cursor() const { return 0; }
 
+void CCoinsView::FindScriptPubKey(CCoinsViewCursor& cursor, const std::set<CScript>& setscriptNeedles, std::map<uint256, CCoins>& outResults) {
+    for ( ; cursor.Valid(); cursor.Next()) {
+        uint256 hash;
+        CCoins coins;
+        if (!cursor.GetKey(hash)) {
+            throw std::runtime_error(std::string(__func__) + ": GetKey failed");
+        } else if (!cursor.GetValue(coins)) {
+            throw std::runtime_error(std::string(__func__) + ": GetValue failed");
+        }
+        bool fFoundAny = false;
+        for (CTxOut& txo : coins.vout) {
+            if (setscriptNeedles.find(txo.scriptPubKey) == setscriptNeedles.end()) {
+                txo.SetNull();
+            } else {
+                fFoundAny = true;
+            }
+        }
+        if (!fFoundAny) {
+            continue;
+        }
+        coins.Cleanup();
+        outResults.insert(std::pair<uint256, CCoins>(hash, coins));
+    }
+}
+
+void CCoinsView::FindScriptPubKey(const std::set<CScript>& setscriptNeedles, std::map<uint256, CCoins>& outResults) {
+    std::unique_ptr<CCoinsViewCursor> pcursor(Cursor());
+    FindScriptPubKey(*pcursor, setscriptNeedles, outResults);
+}
+
 
 CCoinsViewBacked::CCoinsViewBacked(CCoinsView *viewIn) : base(viewIn) { }
 bool CCoinsViewBacked::GetCoins(const uint256 &txid, CCoins &coins) const { return base->GetCoins(txid, coins); }

src/coins.h

@@ -16,6 +16,9 @@
 #include <assert.h>
 #include <stdint.h>
 
+#include <map>
+#include <set>
+
 #include <boost/foreach.hpp>
 #include <boost/unordered_map.hpp>
 
@@ -316,6 +319,10 @@ class CCoinsView
     //! Retrieve the block hash whose state this CCoinsView currently represents
     virtual uint256 GetBestBlock() const;
 
+    //! Search for a given set of pubkey scripts
+    static void FindScriptPubKey(CCoinsViewCursor& cursor, const std::set<CScript>& setscriptNeedles, std::map<uint256, CCoins>& outResults);
+    void FindScriptPubKey(const std::set<CScript>& setscriptNeedles, std::map<uint256, CCoins>& outResults);
+
     //! Do a bulk modification (multiple CCoins changes + BestBlock change).
     //! The passed mapCoins can be modified.
     virtual bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);

src/qt/rpcconsole.cpp

@@ -72,6 +72,7 @@ const QStringList historyFilter = QStringList()
     << "importmulti"
     << "signmessagewithprivkey"
     << "signrawtransaction"
+    << "sweepprivkeys"
     << "walletpassphrase"
     << "walletpassphrasechange"
     << "encryptwallet";

src/rpc/client.cpp

@@ -72,6 +72,7 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "sendmany", 1, "amounts" },
     { "sendmany", 2, "minconf" },
     { "sendmany", 4, "subtractfeefrom" },
+    { "sweepprivkeys", 0, "options" },
     { "addmultisigaddress", 0, "nrequired" },
     { "addmultisigaddress", 1, "keys" },
     { "createmultisig", 0, "nrequired" },

src/txdb.h

@@ -61,7 +61,9 @@ struct CDiskTxPos : public CDiskBlockPos
     }
 };
 
-/** CCoinsView backed by the coin database (chainstate/) */
+/** CCoinsView backed by the coin database (chainstate/)
+ * Cursor requires FlushStateToDisk for consistency.
+ */
 class CCoinsViewDB : public CCoinsView
 {
 protected:

src/txmempool.cpp

@@ -863,6 +863,33 @@ TxMempoolInfo CTxMemPool::info(const uint256& hash) const
     return GetInfo(i);
 }
 
+void CTxMemPool::FindScriptPubKey(const std::set<CScript>& setscriptNeedles, std::map<uint256, CCoins>& outResults) {
+    LOCK(cs);
+    for (const CTxMemPoolEntry& entry : mapTx) {
+        const CTransaction& tx = entry.GetTx();
+        bool fFoundAny = false;
+        for (const CTxOut& txo : tx.vout) {
+            if (setscriptNeedles.find(txo.scriptPubKey) != setscriptNeedles.end()) {
+                fFoundAny = true;
+                break;
+            }
+        }
+        if (!fFoundAny) {
+            continue;
+        }
+
+        const uint256& hash = tx.GetHash();
+        CCoins coins(tx, MEMPOOL_HEIGHT);
+        for (CTxOut& txo : coins.vout) {
+            if (setscriptNeedles.find(txo.scriptPubKey) == setscriptNeedles.end()) {
+                txo.SetNull();
+            }
+        }
+        coins.Cleanup();
+        outResults.insert(std::pair<uint256, CCoins>(hash, coins));
+    }
+}
+
 CFeeRate CTxMemPool::estimateFee(int nBlocks) const
 {
     LOCK(cs);

src/txmempool.h

@@ -6,6 +6,7 @@
 #ifndef BITCOIN_TXMEMPOOL_H
 #define BITCOIN_TXMEMPOOL_H
 
+#include <map>
 #include <memory>
 #include <set>
 #include <map>
@@ -29,6 +30,7 @@
 
 class CAutoFile;
 class CBlockIndex;
+class CScript;
 
 inline double AllowFreeThreshold()
 {
@@ -639,6 +641,8 @@ class CTxMemPool
     TxMempoolInfo info(const uint256& hash) const;
     std::vector<TxMempoolInfo> infoAll() const;
 
+    void FindScriptPubKey(const std::set<CScript>& setscriptNeedles, std::map<uint256, CCoins>& outResults);
+
     /** Estimate fee rate needed to get into the next nBlocks
      *  If no answer can be given at nBlocks, return an estimate
      *  at the lowest number of blocks where one can be given
@@ -708,6 +712,7 @@ class CTxMemPool
 /** 
  * CCoinsView that brings transactions from a memorypool into view.
  * It does not check for spendings by memory pool transactions.
+ * Its Cursor also doesn't work. In general, it is broken as a CCoinsView implementation outside of a few use cases.
  */
 class CCoinsViewMemPool : public CCoinsViewBacked
 {

src/wallet/rpcdump.cpp

@@ -75,6 +75,8 @@ std::string DecodeDumpString(const std::string &str) {
     return ret.str();
 }
 
+void ParseWIFPrivKey(const std::string strSecret, CKey& key, CPubKey& pubkey);
+
 UniValue importprivkey(const JSONRPCRequest& request)
 {
     if (!EnsureWalletIsAvailable(request.fHelp))
@@ -118,16 +120,9 @@ UniValue importprivkey(const JSONRPCRequest& request)
     if (fRescan && fPruneMode)
         throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled in pruned mode");
 
-    CBitcoinSecret vchSecret;
-    bool fGood = vchSecret.SetString(strSecret);
-
-    if (!fGood) throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid private key encoding");
-
-    CKey key = vchSecret.GetKey();
-    if (!key.IsValid()) throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Private key outside allowed range");
-
-    CPubKey pubkey = key.GetPubKey();
-    assert(key.VerifyPubKey(pubkey));
+    CKey key;
+    CPubKey pubkey;
+    ParseWIFPrivKey(strSecret, key, pubkey);
     CKeyID vchAddress = pubkey.GetID();
     {
         pwalletMain->MarkDirty();
@@ -752,21 +747,9 @@ UniValue processImport(const UniValue& data) {
                 for (size_t i = 0; i < keys.size(); i++) {
                     const string& privkey = keys[i].get_str();
 
-                    CBitcoinSecret vchSecret;
-                    bool fGood = vchSecret.SetString(privkey);
-
-                    if (!fGood) {
-                        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid private key encoding");
-                    }
-
-                    CKey key = vchSecret.GetKey();
-
-                    if (!key.IsValid()) {
-                        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Private key outside allowed range");
-                    }
-
-                    CPubKey pubkey = key.GetPubKey();
-                    assert(key.VerifyPubKey(pubkey));
+                    CKey key;
+                    CPubKey pubkey;
+                    ParseWIFPrivKey(privkey, key, pubkey);
 
                     CKeyID vchAddress = pubkey.GetID();
                     pwalletMain->MarkDirty();
@@ -862,21 +845,9 @@ UniValue processImport(const UniValue& data) {
             if (keys.size()) {
                 const string& strPrivkey = keys[0].get_str();
 
-                // Checks.
-                CBitcoinSecret vchSecret;
-                bool fGood = vchSecret.SetString(strPrivkey);
-
-                if (!fGood) {
-                    throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid private key encoding");
-                }
-
-                CKey key = vchSecret.GetKey();
-                if (!key.IsValid()) {
-                    throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Private key outside allowed range");
-                }
-
-                CPubKey pubKey = key.GetPubKey();
-                assert(key.VerifyPubKey(pubKey));
+                CKey key;
+                CPubKey pubKey;
+                ParseWIFPrivKey(strPrivkey, key, pubKey);
 
                 CBitcoinAddress pubKeyAddress = CBitcoinAddress(pubKey.GetID());