Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2021 The Bitcoin Core developers
       3             : // Distributed under the MIT software license, see the accompanying
       4             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       5             : 
       6             : #include <chainparams.h>
       7             : #include <common/args.h>
       8             : #include <logging.h>
       9             : #include <util/fs.h>
      10             : #include <wallet/db.h>
      11             : 
      12             : #include <exception>
      13             : #include <fstream>
      14             : #include <string>
      15             : #include <system_error>
      16             : #include <vector>
      17             : 
      18             : namespace wallet {
      19           0 : std::vector<fs::path> ListDatabases(const fs::path& wallet_dir)
      20             : {
      21           0 :     std::vector<fs::path> paths;
      22           0 :     std::error_code ec;
      23             : 
      24           0 :     for (auto it = fs::recursive_directory_iterator(wallet_dir, ec); it != fs::recursive_directory_iterator(); it.increment(ec)) {
      25           0 :         if (ec) {
      26           0 :             if (fs::is_directory(*it)) {
      27           0 :                 it.disable_recursion_pending();
      28           0 :                 LogPrintf("%s: %s %s -- skipping.\n", __func__, ec.message(), fs::PathToString(it->path()));
      29           0 :             } else {
      30           0 :                 LogPrintf("%s: %s %s\n", __func__, ec.message(), fs::PathToString(it->path()));
      31             :             }
      32           0 :             continue;
      33             :         }
      34             : 
      35             :         try {
      36           0 :             const fs::path path{it->path().lexically_relative(wallet_dir)};
      37             : 
      38           0 :             if (it->status().type() == fs::file_type::directory &&
      39           0 :                 (IsBDBFile(BDBDataFile(it->path())) || IsSQLiteFile(SQLiteDataFile(it->path())))) {
      40             :                 // Found a directory which contains wallet.dat btree file, add it as a wallet.
      41           0 :                 paths.emplace_back(path);
      42           0 :             } else if (it.depth() == 0 && it->symlink_status().type() == fs::file_type::regular && IsBDBFile(it->path())) {
      43           0 :                 if (it->path().filename() == "wallet.dat") {
      44             :                     // Found top-level wallet.dat btree file, add top level directory ""
      45             :                     // as a wallet.
      46           0 :                     paths.emplace_back();
      47           0 :                 } else {
      48             :                     // Found top-level btree file not called wallet.dat. Current bitcoin
      49             :                     // software will never create these files but will allow them to be
      50             :                     // opened in a shared database environment for backwards compatibility.
      51             :                     // Add it to the list of available wallets.
      52           0 :                     paths.emplace_back(path);
      53             :                 }
      54           0 :             }
      55           0 :         } catch (const std::exception& e) {
      56           0 :             LogPrintf("%s: Error scanning %s: %s\n", __func__, fs::PathToString(it->path()), e.what());
      57           0 :             it.disable_recursion_pending();
      58           0 :         }
      59           0 :     }
      60             : 
      61           0 :     return paths;
      62           0 : }
      63             : 
      64           0 : fs::path BDBDataFile(const fs::path& wallet_path)
      65             : {
      66           0 :     if (fs::is_regular_file(wallet_path)) {
      67             :         // Special case for backwards compatibility: if wallet path points to an
      68             :         // existing file, treat it as the path to a BDB data file in a parent
      69             :         // directory that also contains BDB log files.
      70           0 :         return wallet_path;
      71             :     } else {
      72             :         // Normal case: Interpret wallet path as a directory path containing
      73             :         // data and log files.
      74           2 :         return wallet_path / "wallet.dat";
      75             :     }
      76           0 : }
      77             : 
      78           0 : fs::path SQLiteDataFile(const fs::path& path)
      79             : {
      80           0 :     return path / "wallet.dat";
      81           0 : }
      82             : 
      83           0 : bool IsBDBFile(const fs::path& path)
      84             : {
      85           0 :     if (!fs::exists(path)) return false;
      86             : 
      87             :     // A Berkeley DB Btree file has at least 4K.
      88             :     // This check also prevents opening lock files.
      89           0 :     std::error_code ec;
      90           0 :     auto size = fs::file_size(path, ec);
      91           0 :     if (ec) LogPrintf("%s: %s %s\n", __func__, ec.message(), fs::PathToString(path));
      92           0 :     if (size < 4096) return false;
      93             : 
      94           0 :     std::ifstream file{path, std::ios::binary};
      95           0 :     if (!file.is_open()) return false;
      96             : 
      97           0 :     file.seekg(12, std::ios::beg); // Magic bytes start at offset 12
      98           0 :     uint32_t data = 0;
      99           0 :     file.read((char*) &data, sizeof(data)); // Read 4 bytes of file to compare against magic
     100             : 
     101             :     // Berkeley DB Btree magic bytes, from:
     102             :     //  https://github.com/file/file/blob/5824af38469ec1ca9ac3ffd251e7afe9dc11e227/magic/Magdir/database#L74-L75
     103             :     //  - big endian systems - 00 05 31 62
     104             :     //  - little endian systems - 62 31 05 00
     105           0 :     return data == 0x00053162 || data == 0x62310500;
     106           0 : }
     107             : 
     108           0 : bool IsSQLiteFile(const fs::path& path)
     109             : {
     110           0 :     if (!fs::exists(path)) return false;
     111             : 
     112             :     // A SQLite Database file is at least 512 bytes.
     113           0 :     std::error_code ec;
     114           0 :     auto size = fs::file_size(path, ec);
     115           0 :     if (ec) LogPrintf("%s: %s %s\n", __func__, ec.message(), fs::PathToString(path));
     116           0 :     if (size < 512) return false;
     117             : 
     118           0 :     std::ifstream file{path, std::ios::binary};
     119           0 :     if (!file.is_open()) return false;
     120             : 
     121             :     // Magic is at beginning and is 16 bytes long
     122             :     char magic[16];
     123           0 :     file.read(magic, 16);
     124             : 
     125             :     // Application id is at offset 68 and 4 bytes long
     126           0 :     file.seekg(68, std::ios::beg);
     127             :     char app_id[4];
     128           0 :     file.read(app_id, 4);
     129             : 
     130           0 :     file.close();
     131             : 
     132             :     // Check the magic, see https://sqlite.org/fileformat2.html
     133           0 :     std::string magic_str(magic, 16);
     134           0 :     if (magic_str != std::string("SQLite format 3", 16)) {
     135           0 :         return false;
     136             :     }
     137             : 
     138             :     // Check the application id matches our network magic
     139           0 :     return memcmp(Params().MessageStart().data(), app_id, 4) == 0;
     140           0 : }
     141             : 
     142           0 : void ReadDatabaseArgs(const ArgsManager& args, DatabaseOptions& options)
     143             : {
     144             :     // Override current options with args values, if any were specified
     145           0 :     options.use_unsafe_sync = args.GetBoolArg("-unsafesqlitesync", options.use_unsafe_sync);
     146           0 :     options.use_shared_memory = !args.GetBoolArg("-privdb", !options.use_shared_memory);
     147           0 :     options.max_log_mb = args.GetIntArg("-dblogsize", options.max_log_mb);
     148           0 : }
     149             : 
     150             : } // namespace wallet