wallettool: Add createfromdump command

Creates a new wallet file using the dump file produced by the dump
command

src/bitcoin-wallet.cpp

@@ -27,15 +27,17 @@ static void SetupWalletToolArgs(ArgsManager& argsman)
     argsman.AddArg("-version", "Print version and exit", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-datadir=<dir>", "Specify data directory", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-wallet=<wallet-name>", "Specify wallet name", ArgsManager::ALLOW_ANY | ArgsManager::NETWORK_ONLY, OptionsCategory::OPTIONS);
-    argsman.AddArg("-dumpfile=<file name>", "When used with 'dump', writes out the records to this file.", ArgsManager::ALLOW_STRING, OptionsCategory::OPTIONS);
+    argsman.AddArg("-dumpfile=<file name>", "When used with 'dump', writes out the records to this file. When used with 'createfromdump', loads the records into a new wallet.", ArgsManager::ALLOW_STRING, OptionsCategory::OPTIONS);
     argsman.AddArg("-debug=<category>", "Output debugging information (default: 0).", ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
     argsman.AddArg("-descriptors", "Create descriptors wallet. Only for create", ArgsManager::ALLOW_BOOL, OptionsCategory::OPTIONS);
+    argsman.AddArg("-format=<format>", "The format of the wallet file to create. Either \"bdb\" or \"sqlite\". Only used with 'createfromdump'", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-printtoconsole", "Send trace/debug info to console (default: 1 when no -debug is true, 0 otherwise).", ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
 
     argsman.AddArg("info", "Get wallet info", ArgsManager::ALLOW_ANY, OptionsCategory::COMMANDS);
     argsman.AddArg("create", "Create new wallet file", ArgsManager::ALLOW_ANY, OptionsCategory::COMMANDS);
     argsman.AddArg("salvage", "Attempt to recover private keys from a corrupt wallet. Warning: 'salvage' is experimental.", ArgsManager::ALLOW_ANY, OptionsCategory::COMMANDS);
     argsman.AddArg("dump", "Print out all of the wallet key-value records", ArgsManager::ALLOW_ANY, OptionsCategory::COMMANDS);
+    argsman.AddArg("createfromdump", "Create new wallet file from dumped records", ArgsManager::ALLOW_ANY, OptionsCategory::COMMANDS);
 }
 
 static bool WalletAppInit(int argc, char* argv[])

src/wallet/dump.cpp

@@ -94,3 +94,189 @@ bool DumpWallet(CWallet& wallet, bilingual_str& error)
 
     return ret;
 }
+
+// The standard wallet deleter function blocks on the validation interface
+// queue, which doesn't exist for the bitcoin-wallet. Define our own
+// deleter here.
+static void WalletToolReleaseWallet(CWallet* wallet)
+{
+    wallet->WalletLogPrintf("Releasing wallet\n");
+    wallet->Close();
+    delete wallet;
+}
+
+bool CreateFromDump(const std::string& name, const fs::path& wallet_path, bilingual_str& error, std::vector<bilingual_str>& warnings)
+{
+    // Get the dumpfile
+    std::string dump_filename = gArgs.GetArg("-dumpfile", "");
+    if (dump_filename.empty()) {
+        error = _("No dump file provided. To use createfromdump, -dumpfile=<filename> must be provided.");
+        return false;
+    }
+
+    fs::path dump_path = dump_filename;
+    dump_path = fs::absolute(dump_path);
+    if (!fs::exists(dump_path)) {
+        error = strprintf(_("Dump file %s does not exist."), dump_path.string());
+        return false;
+    }
+    fsbridge::ifstream dump_file(dump_path);
+
+    // Compute the checksum
+    CHashWriter hasher(0, 0);
+    uint256 checksum;
+
+    // Check the magic and version
+    std::string magic_key;
+    std::getline(dump_file, magic_key, ',');
+    std::string version_value;
+    std::getline(dump_file, version_value, '\n');
+    if (magic_key != DUMP_MAGIC) {
+        error = strprintf(_("Error: Dumpfile identifier record is incorrect. Got \"%s\", expected \"%s\"."), magic_key, DUMP_MAGIC);
+        dump_file.close();
+        return false;
+    }
+    // Check the version number (value of first record)
+    uint32_t ver;
+    if (!ParseUInt32(version_value, &ver)) {
+        error =strprintf(_("Error: Unable to parse version %u as a uint32_t"), version_value);
+        dump_file.close();
+        return false;
+    }
+    if (ver != DUMP_VERSION) {
+        error = strprintf(_("Error: Dumpfile version is not supported. This version of bitcoin-wallet only supports version 1 dumpfiles. Got dumpfile with version %s"), version_value);
+        dump_file.close();
+        return false;
+    }
+    std::string magic_hasher_line = strprintf("%s,%s\n", magic_key, version_value);
+    hasher.write(magic_hasher_line.data(), magic_hasher_line.size());
+
+    // Get the stored file format
+    std::string format_key;
+    std::getline(dump_file, format_key, ',');
+    std::string format_value;
+    std::getline(dump_file, format_value, '\n');
+    if (format_key != "format") {
+        error = strprintf(_("Error: Dumpfile format record is incorrect. Got \"%s\", expected \"format\"."), format_key);
+        dump_file.close();
+        return false;
+    }
+    // Get the data file format with format_value as the default
+    std::string file_format = gArgs.GetArg("-format", format_value);
+    if (file_format.empty()) {
+        error = _("No wallet file format provided. To use createfromdump, -format=<format> must be provided.");
+        return false;
+    }
+    DatabaseFormat data_format;
+    if (file_format == "bdb") {
+        data_format = DatabaseFormat::BERKELEY;
+    } else if (file_format == "sqlite") {
+        data_format = DatabaseFormat::SQLITE;
+    } else {
+        error = strprintf(_("Unknown wallet file format \"%s\" provided. Please provide one of \"bdb\" or \"sqlite\"."), file_format);
+        return false;
+    }
+    if (file_format != format_value) {
+        warnings.push_back(strprintf(_("Warning: Dumpfile wallet format \"%s\" does not match command line specified format \"%s\"."), format_value, file_format));
+    }
+    std::string format_hasher_line = strprintf("%s,%s\n", format_key, format_value);
+    hasher.write(format_hasher_line.data(), format_hasher_line.size());
+
+    DatabaseOptions options;
+    DatabaseStatus status;
+    options.require_create = true;
+    options.require_format = data_format;
+    std::unique_ptr<WalletDatabase> database = MakeDatabase(wallet_path, options, status, error);
+    if (!database) return false;
+
+    // dummy chain interface
+    bool ret = true;
+    std::shared_ptr<CWallet> wallet(new CWallet(nullptr /* chain */, name, std::move(database)), WalletToolReleaseWallet);
+    {
+        LOCK(wallet->cs_wallet);
+        bool first_run = true;
+        DBErrors load_wallet_ret = wallet->LoadWallet(first_run);
+        if (load_wallet_ret != DBErrors::LOAD_OK) {
+            error = strprintf(_("Error creating %s"), name);
+            return false;
+        }
+
+        // Get the database handle
+        WalletDatabase& db = wallet->GetDatabase();
+        std::unique_ptr<DatabaseBatch> batch = db.MakeBatch();
+        batch->TxnBegin();
+
+        // Read the records from the dump file and write them to the database
+        while (dump_file.good()) {
+            std::string key;
+            std::getline(dump_file, key, ',');
+            std::string value;
+            std::getline(dump_file, value, '\n');
+
+            if (key == "checksum") {
+                std::vector<unsigned char> parsed_checksum = ParseHex(value);
+                std::copy(parsed_checksum.begin(), parsed_checksum.end(), checksum.begin());
+                break;
+            }
+
+            std::string line = strprintf("%s,%s\n", key, value);
+            hasher.write(line.data(), line.size());
+
+            if (key.empty() || value.empty()) {
+                continue;
+            }
+
+            if (!IsHex(key)) {
+                error = strprintf(_("Error: Got key that was not hex: %s"), key);
+                ret = false;
+                break;
+            }
+            if (!IsHex(value)) {
+                error = strprintf(_("Error: Got value that was not hex: %s"), value);
+                ret = false;
+                break;
+            }
+
+            std::vector<unsigned char> k = ParseHex(key);
+            std::vector<unsigned char> v = ParseHex(value);
+
+            CDataStream ss_key(k, SER_DISK, CLIENT_VERSION);
+            CDataStream ss_value(v, SER_DISK, CLIENT_VERSION);
+
+            if (!batch->Write(ss_key, ss_value)) {
+                error = strprintf(_("Error: Unable to write record to new wallet"));
+                ret = false;
+                break;
+            }
+        }
+
+        if (ret) {
+            uint256 comp_checksum = hasher.GetHash();
+            if (checksum.IsNull()) {
+                error = _("Error: Missing checksum");
+                ret = false;
+            } else if (checksum != comp_checksum) {
+                error = strprintf(_("Error: Dumpfile checksum does not match. Computed %s, expected %s"), HexStr(comp_checksum), HexStr(checksum));
+                ret = false;
+            }
+        }
+
+        if (ret) {
+            batch->TxnCommit();
+        } else {
+            batch->TxnAbort();
+        }
+
+        batch.reset();
+
+        dump_file.close();
+    }
+    wallet.reset(); // The pointer deleter will close the wallet for us.
+
+    // Remove the wallet dir if we have a failure
+    if (!ret) {
+        fs::remove_all(wallet_path);
+    }
+
+    return ret;
+}

src/wallet/dump.h

@@ -5,10 +5,13 @@
 #ifndef BITCOIN_WALLET_DUMP_H
 #define BITCOIN_WALLET_DUMP_H
 
+#include <fs.h>
+
 class CWallet;
 
 struct bilingual_str;
 
 bool DumpWallet(CWallet& wallet, bilingual_str& error);
+bool CreateFromDump(const std::string& name, const fs::path& wallet_path, bilingual_str& error, std::vector<bilingual_str>& warnings);
 
 #endif // BITCOIN_WALLET_DUMP_H

src/wallet/wallettool.cpp

@@ -107,6 +107,11 @@ bool ExecuteWalletToolFunc(const std::string& command, const std::string& name)
 {
     fs::path path = fs::absolute(name, GetWalletDir());
 
+    // -format is only allowed with createfromdump. Disallow it for all other commands.
+    if (gArgs.IsArgSet("-format") && command != "createfromdump") {
+        tfm::format(std::cerr, "The -format option can only be used with the \"createfromdump\" command.\n");
+        return false;
+    }
     // -dumpfile is only allowed with dump and createfromdump. Disallow it for all other commands.
     if (gArgs.IsArgSet("-dumpfile") && command != "dump" && command != "createfromdump") {
         tfm::format(std::cerr, "The -dumpfile option can only be used with the \"dump\" and \"createfromdump\" commands.\n");
@@ -164,6 +169,17 @@ bool ExecuteWalletToolFunc(const std::string& command, const std::string& name)
         }
         tfm::format(std::cout, "The dumpfile may contain private keys. To ensure the safety of your Bitcoin, do not share the dumpfile.\n");
         return ret;
+    } else if (command == "createfromdump") {
+        bilingual_str error;
+        std::vector<bilingual_str> warnings;
+        bool ret = CreateFromDump(name, path, error, warnings);
+        for (const auto& warning : warnings) {
+            tfm::format(std::cout, "%s\n", warning.original);
+        }
+        if (!ret && !error.empty()) {
+            tfm::format(std::cerr, "%s\n", error.original);
+        }
+        return ret;
     } else {
         tfm::format(std::cerr, "Invalid command: %s\n", command);
         return false;