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Diffstat (limited to 'src/dbwrapper.cpp')
| -rw-r--r-- | src/dbwrapper.cpp | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/src/dbwrapper.cpp b/src/dbwrapper.cpp new file mode 100644 index 0000000000..dfc90f3ab9 --- /dev/null +++ b/src/dbwrapper.cpp @@ -0,0 +1,218 @@ +// Copyright (c) 2012-2016 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include "dbwrapper.h" + +#include "fs.h" +#include "util.h" +#include "random.h" + +#include <leveldb/cache.h> +#include <leveldb/env.h> +#include <leveldb/filter_policy.h> +#include <memenv.h> +#include <stdint.h> +#include <algorithm> + +class CBitcoinLevelDBLogger : public leveldb::Logger { +public: + // This code is adapted from posix_logger.h, which is why it is using vsprintf. + // Please do not do this in normal code + void Logv(const char * format, va_list ap) override { + if (!LogAcceptCategory(BCLog::LEVELDB)) { + return; + } + char buffer[500]; + for (int iter = 0; iter < 2; iter++) { + char* base; + int bufsize; + if (iter == 0) { + bufsize = sizeof(buffer); + base = buffer; + } + else { + bufsize = 30000; + base = new char[bufsize]; + } + char* p = base; + char* limit = base + bufsize; + + // Print the message + if (p < limit) { + va_list backup_ap; + va_copy(backup_ap, ap); + // Do not use vsnprintf elsewhere in bitcoin source code, see above. + p += vsnprintf(p, limit - p, format, backup_ap); + va_end(backup_ap); + } + + // Truncate to available space if necessary + if (p >= limit) { + if (iter == 0) { + continue; // Try again with larger buffer + } + else { + p = limit - 1; + } + } + + // Add newline if necessary + if (p == base || p[-1] != '\n') { + *p++ = '\n'; + } + + assert(p <= limit); + base[std::min(bufsize - 1, (int)(p - base))] = '\0'; + LogPrintStr(base); + if (base != buffer) { + delete[] base; + } + break; + } + } +}; + +static leveldb::Options GetOptions(size_t nCacheSize) +{ + leveldb::Options options; + options.block_cache = leveldb::NewLRUCache(nCacheSize / 2); + options.write_buffer_size = nCacheSize / 4; // up to two write buffers may be held in memory simultaneously + options.filter_policy = leveldb::NewBloomFilterPolicy(10); + options.compression = leveldb::kNoCompression; + options.max_open_files = 64; + options.info_log = new CBitcoinLevelDBLogger(); + if (leveldb::kMajorVersion > 1 || (leveldb::kMajorVersion == 1 && leveldb::kMinorVersion >= 16)) { + // LevelDB versions before 1.16 consider short writes to be corruption. Only trigger error + // on corruption in later versions. + options.paranoid_checks = true; + } + return options; +} + +CDBWrapper::CDBWrapper(const fs::path& path, size_t nCacheSize, bool fMemory, bool fWipe, bool obfuscate) +{ + penv = nullptr; + readoptions.verify_checksums = true; + iteroptions.verify_checksums = true; + iteroptions.fill_cache = false; + syncoptions.sync = true; + options = GetOptions(nCacheSize); + options.create_if_missing = true; + if (fMemory) { + penv = leveldb::NewMemEnv(leveldb::Env::Default()); + options.env = penv; + } else { + if (fWipe) { + LogPrintf("Wiping LevelDB in %s\n", path.string()); + leveldb::Status result = leveldb::DestroyDB(path.string(), options); + dbwrapper_private::HandleError(result); + } + TryCreateDirectories(path); + LogPrintf("Opening LevelDB in %s\n", path.string()); + } + leveldb::Status status = leveldb::DB::Open(options, path.string(), &pdb); + dbwrapper_private::HandleError(status); + LogPrintf("Opened LevelDB successfully\n"); + + if (gArgs.GetBoolArg("-forcecompactdb", false)) { + LogPrintf("Starting database compaction of %s\n", path.string()); + pdb->CompactRange(nullptr, nullptr); + LogPrintf("Finished database compaction of %s\n", path.string()); + } + + // The base-case obfuscation key, which is a noop. + obfuscate_key = std::vector<unsigned char>(OBFUSCATE_KEY_NUM_BYTES, '\000'); + + bool key_exists = Read(OBFUSCATE_KEY_KEY, obfuscate_key); + + if (!key_exists && obfuscate && IsEmpty()) { + // Initialize non-degenerate obfuscation if it won't upset + // existing, non-obfuscated data. + std::vector<unsigned char> new_key = CreateObfuscateKey(); + + // Write `new_key` so we don't obfuscate the key with itself + Write(OBFUSCATE_KEY_KEY, new_key); + obfuscate_key = new_key; + + LogPrintf("Wrote new obfuscate key for %s: %s\n", path.string(), HexStr(obfuscate_key)); + } + + LogPrintf("Using obfuscation key for %s: %s\n", path.string(), HexStr(obfuscate_key)); +} + +CDBWrapper::~CDBWrapper() +{ + delete pdb; + pdb = nullptr; + delete options.filter_policy; + options.filter_policy = nullptr; + delete options.info_log; + options.info_log = nullptr; + delete options.block_cache; + options.block_cache = nullptr; + delete penv; + options.env = nullptr; +} + +bool CDBWrapper::WriteBatch(CDBBatch& batch, bool fSync) +{ + leveldb::Status status = pdb->Write(fSync ? syncoptions : writeoptions, &batch.batch); + dbwrapper_private::HandleError(status); + return true; +} + +// Prefixed with null character to avoid collisions with other keys +// +// We must use a string constructor which specifies length so that we copy +// past the null-terminator. +const std::string CDBWrapper::OBFUSCATE_KEY_KEY("\000obfuscate_key", 14); + +const unsigned int CDBWrapper::OBFUSCATE_KEY_NUM_BYTES = 8; + +/** + * Returns a string (consisting of 8 random bytes) suitable for use as an + * obfuscating XOR key. + */ +std::vector<unsigned char> CDBWrapper::CreateObfuscateKey() const +{ + unsigned char buff[OBFUSCATE_KEY_NUM_BYTES]; + GetRandBytes(buff, OBFUSCATE_KEY_NUM_BYTES); + return std::vector<unsigned char>(&buff[0], &buff[OBFUSCATE_KEY_NUM_BYTES]); + +} + +bool CDBWrapper::IsEmpty() +{ + std::unique_ptr<CDBIterator> it(NewIterator()); + it->SeekToFirst(); + return !(it->Valid()); +} + +CDBIterator::~CDBIterator() { delete piter; } +bool CDBIterator::Valid() const { return piter->Valid(); } +void CDBIterator::SeekToFirst() { piter->SeekToFirst(); } +void CDBIterator::Next() { piter->Next(); } + +namespace dbwrapper_private { + +void HandleError(const leveldb::Status& status) +{ + if (status.ok()) + return; + LogPrintf("%s\n", status.ToString()); + if (status.IsCorruption()) + throw dbwrapper_error("Database corrupted"); + if (status.IsIOError()) + throw dbwrapper_error("Database I/O error"); + if (status.IsNotFound()) + throw dbwrapper_error("Database entry missing"); + throw dbwrapper_error("Unknown database error"); +} + +const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w) +{ + return w.obfuscate_key; +} + +} // namespace dbwrapper_private |