implement importelectrumwallet (#1377)

Imports keys from an Electrum wallet export file (.csv or .json)

src/rpcclient.cpp

@@ -99,6 +99,7 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "lockunspent", 0 },
     { "lockunspent", 1 },
     { "importprivkey", 2 },
+    { "importelectrumwallet", 1 },
     { "importaddress", 2 },
     { "importaddress", 3 },
     { "importpubkey", 2 },

src/rpcserver.cpp

@@ -378,6 +378,7 @@ static const CRPCCommand vRPCCommands[] =
     { "wallet",             "getwalletinfo",          &getwalletinfo,          false },
     { "wallet",             "importprivkey",          &importprivkey,          true  },
     { "wallet",             "importwallet",           &importwallet,           true  },
+    { "wallet",             "importelectrumwallet",   &importelectrumwallet,   true  },
     { "wallet",             "importaddress",          &importaddress,          true  },
     { "wallet",             "importpubkey",           &importpubkey,           true  },
     { "wallet",             "keypoolrefill",          &keypoolrefill,          true  },

src/rpcserver.h

@@ -194,6 +194,7 @@ extern UniValue importaddress(const UniValue& params, bool fHelp);
 extern UniValue importpubkey(const UniValue& params, bool fHelp);
 extern UniValue dumpwallet(const UniValue& params, bool fHelp);
 extern UniValue importwallet(const UniValue& params, bool fHelp);
+extern UniValue importelectrumwallet(const UniValue& params, bool fHelp);
 
 extern UniValue getgenerate(const UniValue& params, bool fHelp); // in rpcmining.cpp
 extern UniValue setgenerate(const UniValue& params, bool fHelp);

src/wallet/rpcdump.cpp

@@ -409,6 +409,140 @@ UniValue importwallet(const UniValue& params, bool fHelp)
     return NullUniValue;
 }
 
+UniValue importelectrumwallet(const UniValue& params, bool fHelp)
+{
+    if (!EnsureWalletIsAvailable(fHelp))
+        return NullUniValue;
+
+    if (fHelp || params.size() < 1 || params.size() > 2)
+        throw runtime_error(
+            "importelectrumwallet \"filename\" index\n"
+            "\nImports keys from an Electrum wallet export file (.csv or .json)\n"
+            "\nArguments:\n"
+            "1. \"filename\"    (string, required) The Electrum wallet export file, should be in csv or json format\n"
+            "2. index         (numeric, optional, default=0) Rescan the wallet for transactions starting from this block index\n"
+            "\nExamples:\n"
+            "\nImport the wallet\n"
+            + HelpExampleCli("importelectrumwallet", "\"test.csv\"")
+            + HelpExampleCli("importelectrumwallet", "\"test.json\"") +
+            "\nImport using the json rpc call\n"
+            + HelpExampleRpc("importelectrumwallet", "\"test.csv\"")
+            + HelpExampleRpc("importelectrumwallet", "\"test.json\"")
+        );
+
+    if (fPruneMode)
+        throw JSONRPCError(RPC_WALLET_ERROR, "Importing wallets is disabled in pruned mode");
+
+    LOCK2(cs_main, pwalletMain->cs_wallet);
+
+    EnsureWalletIsUnlocked();
+
+    ifstream file;
+    std::string strFileName = params[0].get_str();
+    size_t nDotPos = strFileName.find_last_of(".");
+    if(nDotPos == string::npos)
+        throw JSONRPCError(RPC_INVALID_PARAMETER, "File has no extension, should be .json or .csv");
+
+    std::string strFileExt = strFileName.substr(nDotPos+1);
+    if(strFileExt != "json" && strFileExt != "csv")
+        throw JSONRPCError(RPC_INVALID_PARAMETER, "File has wrong extension, should be .json or .csv");
+
+    file.open(strFileName.c_str(), std::ios::in | std::ios::ate);
+    if (!file.is_open())
+        throw JSONRPCError(RPC_INVALID_PARAMETER, "Cannot open Electrum wallet export file");
+
+    bool fGood = true;
+
+    int64_t nFilesize = std::max((int64_t)1, (int64_t)file.tellg());
+    file.seekg(0, file.beg);
+
+    pwalletMain->ShowProgress(_("Importing..."), 0); // show progress dialog in GUI
+
+    if(strFileExt == "csv") {
+        while (file.good()) {
+            pwalletMain->ShowProgress("", std::max(1, std::min(99, (int)(((double)file.tellg() / (double)nFilesize) * 100))));
+            std::string line;
+            std::getline(file, line);
+            if (line.empty() || line == "address,private_key")
+                continue;
+            std::vector<std::string> vstr;
+            boost::split(vstr, line, boost::is_any_of(","));
+            if (vstr.size() < 2)
+                continue;
+            CBitcoinSecret vchSecret;
+            if (!vchSecret.SetString(vstr[1]))
+                continue;
+            CKey key = vchSecret.GetKey();
+            CPubKey pubkey = key.GetPubKey();
+            assert(key.VerifyPubKey(pubkey));
+            CKeyID keyid = pubkey.GetID();
+            if (pwalletMain->HaveKey(keyid)) {
+                LogPrintf("Skipping import of %s (key already present)\n", CBitcoinAddress(keyid).ToString());
+                continue;
+            }
+            LogPrintf("Importing %s...\n", CBitcoinAddress(keyid).ToString());
+            if (!pwalletMain->AddKeyPubKey(key, pubkey)) {
+                fGood = false;
+                continue;
+            }
+        }
+    } else {
+        // json
+        char* buffer = new char [nFilesize];
+        file.read(buffer, nFilesize);
+        UniValue data(UniValue::VOBJ);
+        if(!data.read(buffer))
+            throw JSONRPCError(RPC_TYPE_ERROR, "Cannot parse Electrum wallet export file");
+        delete[] buffer;
+
+        std::vector<std::string> vKeys = data.getKeys();
+
+        for (size_t i = 0; i < data.size(); i++) {
+            pwalletMain->ShowProgress("", std::max(1, std::min(99, int(i*100/data.size()))));
+            if(!data[vKeys[i]].isStr())
+                continue;
+            CBitcoinSecret vchSecret;
+            if (!vchSecret.SetString(data[vKeys[i]].get_str()))
+                continue;
+            CKey key = vchSecret.GetKey();
+            CPubKey pubkey = key.GetPubKey();
+            assert(key.VerifyPubKey(pubkey));
+            CKeyID keyid = pubkey.GetID();
+            if (pwalletMain->HaveKey(keyid)) {
+                LogPrintf("Skipping import of %s (key already present)\n", CBitcoinAddress(keyid).ToString());
+                continue;
+            }
+            LogPrintf("Importing %s...\n", CBitcoinAddress(keyid).ToString());
+            if (!pwalletMain->AddKeyPubKey(key, pubkey)) {
+                fGood = false;
+                continue;
+            }
+        }
+    }
+    file.close();
+    pwalletMain->ShowProgress("", 100); // hide progress dialog in GUI
+
+    // Whether to perform rescan after import
+    int nStartHeight = 0;
+    if (params.size() > 1)
+        nStartHeight = params[1].get_int();
+    if (chainActive.Height() < nStartHeight)
+        nStartHeight = chainActive.Height();
+
+    // Assume that electrum wallet was created at that block
+    int nTimeBegin = chainActive[nStartHeight]->GetBlockTime();
+    if (!pwalletMain->nTimeFirstKey || nTimeBegin < pwalletMain->nTimeFirstKey)
+        pwalletMain->nTimeFirstKey = nTimeBegin;
+
+    LogPrintf("Rescanning %i blocks\n", chainActive.Height() - nStartHeight + 1);
+    pwalletMain->ScanForWalletTransactions(chainActive[nStartHeight], true);
+
+    if (!fGood)
+        throw JSONRPCError(RPC_WALLET_ERROR, "Error adding some keys to wallet");
+
+    return NullUniValue;
+}
+
 UniValue dumpprivkey(const UniValue& params, bool fHelp)
 {
     if (!EnsureWalletIsAvailable(fHelp))