1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2021 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 <streams.h>
#include <util/fs.h>
#include <util/translation.h>
#include <wallet/bdb.h>
#include <wallet/salvage.h>
#include <wallet/wallet.h>
#include <wallet/walletdb.h>
#include <db_cxx.h>
namespace wallet {
/* End of headers, beginning of key/value data */
static const char *HEADER_END = "HEADER=END";
/* End of key/value data */
static const char *DATA_END = "DATA=END";
typedef std::pair<std::vector<unsigned char>, std::vector<unsigned char> > KeyValPair;
class DummyCursor : public DatabaseCursor
{
Status Next(DataStream& key, DataStream& value) override { return Status::FAIL; }
};
/** RAII class that provides access to a DummyDatabase. Never fails. */
class DummyBatch : public DatabaseBatch
{
private:
bool ReadKey(DataStream&& key, DataStream& value) override { return true; }
bool WriteKey(DataStream&& key, DataStream&& value, bool overwrite=true) override { return true; }
bool EraseKey(DataStream&& key) override { return true; }
bool HasKey(DataStream&& key) override { return true; }
bool ErasePrefix(Span<const std::byte> prefix) override { return true; }
public:
void Flush() override {}
void Close() override {}
std::unique_ptr<DatabaseCursor> GetNewCursor() override { return std::make_unique<DummyCursor>(); }
std::unique_ptr<DatabaseCursor> GetNewPrefixCursor(Span<const std::byte> prefix) override { return GetNewCursor(); }
bool TxnBegin() override { return true; }
bool TxnCommit() override { return true; }
bool TxnAbort() override { return true; }
bool HasActiveTxn() override { return false; }
};
/** A dummy WalletDatabase that does nothing and never fails. Only used by salvage.
**/
class DummyDatabase : public WalletDatabase
{
public:
void Open() override {};
void AddRef() override {}
void RemoveRef() override {}
bool Rewrite(const char* pszSkip=nullptr) override { return true; }
bool Backup(const std::string& strDest) const override { return true; }
void Close() override {}
void Flush() override {}
bool PeriodicFlush() override { return true; }
void IncrementUpdateCounter() override { ++nUpdateCounter; }
void ReloadDbEnv() override {}
std::string Filename() override { return "dummy"; }
std::string Format() override { return "dummy"; }
std::unique_ptr<DatabaseBatch> MakeBatch(bool flush_on_close = true) override { return std::make_unique<DummyBatch>(); }
};
bool RecoverDatabaseFile(const ArgsManager& args, const fs::path& file_path, bilingual_str& error, std::vector<bilingual_str>& warnings)
{
DatabaseOptions options;
DatabaseStatus status;
ReadDatabaseArgs(args, options);
options.require_existing = true;
options.verify = false;
options.require_format = DatabaseFormat::BERKELEY;
std::unique_ptr<WalletDatabase> database = MakeDatabase(file_path, options, status, error);
if (!database) return false;
BerkeleyDatabase& berkeley_database = static_cast<BerkeleyDatabase&>(*database);
std::string filename = berkeley_database.Filename();
std::shared_ptr<BerkeleyEnvironment> env = berkeley_database.env;
if (!env->Open(error)) {
return false;
}
// Recovery procedure:
// move wallet file to walletfilename.timestamp.bak
// Call Salvage with fAggressive=true to
// get as much data as possible.
// Rewrite salvaged data to fresh wallet file
// Rescan so any missing transactions will be
// found.
int64_t now = GetTime();
std::string newFilename = strprintf("%s.%d.bak", filename, now);
int result = env->dbenv->dbrename(nullptr, filename.c_str(), nullptr,
newFilename.c_str(), DB_AUTO_COMMIT);
if (result != 0)
{
error = strprintf(Untranslated("Failed to rename %s to %s"), filename, newFilename);
return false;
}
/**
* Salvage data from a file. The DB_AGGRESSIVE flag is being used (see berkeley DB->verify() method documentation).
* key/value pairs are appended to salvagedData which are then written out to a new wallet file.
* NOTE: reads the entire database into memory, so cannot be used
* for huge databases.
*/
std::vector<KeyValPair> salvagedData;
std::stringstream strDump;
Db db(env->dbenv.get(), 0);
result = db.verify(newFilename.c_str(), nullptr, &strDump, DB_SALVAGE | DB_AGGRESSIVE);
if (result == DB_VERIFY_BAD) {
warnings.push_back(Untranslated("Salvage: Database salvage found errors, all data may not be recoverable."));
}
if (result != 0 && result != DB_VERIFY_BAD) {
error = strprintf(Untranslated("Salvage: Database salvage failed with result %d."), result);
return false;
}
// Format of bdb dump is ascii lines:
// header lines...
// HEADER=END
// hexadecimal key
// hexadecimal value
// ... repeated
// DATA=END
std::string strLine;
while (!strDump.eof() && strLine != HEADER_END)
getline(strDump, strLine); // Skip past header
std::string keyHex, valueHex;
while (!strDump.eof() && keyHex != DATA_END) {
getline(strDump, keyHex);
if (keyHex != DATA_END) {
if (strDump.eof())
break;
getline(strDump, valueHex);
if (valueHex == DATA_END) {
warnings.push_back(Untranslated("Salvage: WARNING: Number of keys in data does not match number of values."));
break;
}
salvagedData.emplace_back(ParseHex(keyHex), ParseHex(valueHex));
}
}
bool fSuccess;
if (keyHex != DATA_END) {
warnings.push_back(Untranslated("Salvage: WARNING: Unexpected end of file while reading salvage output."));
fSuccess = false;
} else {
fSuccess = (result == 0);
}
if (salvagedData.empty())
{
error = strprintf(Untranslated("Salvage(aggressive) found no records in %s."), newFilename);
return false;
}
std::unique_ptr<Db> pdbCopy = std::make_unique<Db>(env->dbenv.get(), 0);
int ret = pdbCopy->open(nullptr, // Txn pointer
filename.c_str(), // Filename
"main", // Logical db name
DB_BTREE, // Database type
DB_CREATE, // Flags
0);
if (ret > 0) {
error = strprintf(Untranslated("Cannot create database file %s"), filename);
pdbCopy->close(0);
return false;
}
DbTxn* ptxn = env->TxnBegin(DB_TXN_WRITE_NOSYNC);
CWallet dummyWallet(nullptr, "", std::make_unique<DummyDatabase>());
for (KeyValPair& row : salvagedData)
{
/* Filter for only private key type KV pairs to be added to the salvaged wallet */
DataStream ssKey{row.first};
DataStream ssValue(row.second);
std::string strType, strErr;
// We only care about KEY, MASTER_KEY, CRYPTED_KEY, and HDCHAIN types
ssKey >> strType;
bool fReadOK = false;
if (strType == DBKeys::KEY) {
fReadOK = LoadKey(&dummyWallet, ssKey, ssValue, strErr);
} else if (strType == DBKeys::CRYPTED_KEY) {
fReadOK = LoadCryptedKey(&dummyWallet, ssKey, ssValue, strErr);
} else if (strType == DBKeys::MASTER_KEY) {
fReadOK = LoadEncryptionKey(&dummyWallet, ssKey, ssValue, strErr);
} else if (strType == DBKeys::HDCHAIN) {
fReadOK = LoadHDChain(&dummyWallet, ssValue, strErr);
} else {
continue;
}
if (!fReadOK)
{
warnings.push_back(strprintf(Untranslated("WARNING: WalletBatch::Recover skipping %s: %s"), strType, strErr));
continue;
}
Dbt datKey(row.first.data(), row.first.size());
Dbt datValue(row.second.data(), row.second.size());
int ret2 = pdbCopy->put(ptxn, &datKey, &datValue, DB_NOOVERWRITE);
if (ret2 > 0)
fSuccess = false;
}
ptxn->commit(0);
pdbCopy->close(0);
return fSuccess;
}
} // namespace wallet
|
