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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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8,885 bytes · SHA-256 99e477b2fe44fb7e… · View upstream ↗

1// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file. See the AUTHORS file for names of contributors.
4
5#include "db/log_reader.h"
6
7#include <stdio.h>
8
9#include "leveldb/env.h"
10#include "util/coding.h"
11#include "util/crc32c.h"
12
13namespace leveldb {
14namespace log {
15
16Reader::Reporter::~Reporter() = default;
17
18Reader::Reader(SequentialFile* file, Reporter* reporter, bool checksum,
19               uint64_t initial_offset)
20    : file_(file),
21      reporter_(reporter),
22      checksum_(checksum),
23      backing_store_(new char[kBlockSize]),
24      buffer_(),
25      eof_(false),
26      last_record_offset_(0),
27      end_of_buffer_offset_(0),
28      initial_offset_(initial_offset),
29      resyncing_(initial_offset > 0) {}
30
31Reader::~Reader() { delete[] backing_store_; }
32
33bool Reader::SkipToInitialBlock() {
34  const size_t offset_in_block = initial_offset_ % kBlockSize;
35  uint64_t block_start_location = initial_offset_ - offset_in_block;
36
37  // Don't search a block if we'd be in the trailer
38  if (offset_in_block > kBlockSize - 6) {
39    block_start_location += kBlockSize;
40  }
41
42  end_of_buffer_offset_ = block_start_location;
43
44  // Skip to start of first block that can contain the initial record
45  if (block_start_location > 0) {
46    Status skip_status = file_->Skip(block_start_location);
47    if (!skip_status.ok()) {
48      ReportDrop(block_start_location, skip_status);
49      return false;
50    }
51  }
52
53  return true;
54}
55
56bool Reader::ReadRecord(Slice* record, std::string* scratch) {
57  if (last_record_offset_ < initial_offset_) {
58    if (!SkipToInitialBlock()) {
59      return false;
60    }
61  }
62
63  scratch->clear();
64  record->clear();
65  bool in_fragmented_record = false;
66  // Record offset of the logical record that we're reading
67  // 0 is a dummy value to make compilers happy
68  uint64_t prospective_record_offset = 0;
69
70  Slice fragment;
71  while (true) {
72    const unsigned int record_type = ReadPhysicalRecord(&fragment);
73
74    // ReadPhysicalRecord may have only had an empty trailer remaining in its
75    // internal buffer. Calculate the offset of the next physical record now
76    // that it has returned, properly accounting for its header size.
77    uint64_t physical_record_offset =
78        end_of_buffer_offset_ - buffer_.size() - kHeaderSize - fragment.size();
79
80    if (resyncing_) {
81      if (record_type == kMiddleType) {
82        continue;
83      } else if (record_type == kLastType) {
84        resyncing_ = false;
85        continue;
86      } else {
87        resyncing_ = false;
88      }
89    }
90
91    switch (record_type) {
92      case kFullType:
93        if (in_fragmented_record) {
94          // Handle bug in earlier versions of log::Writer where
95          // it could emit an empty kFirstType record at the tail end
96          // of a block followed by a kFullType or kFirstType record
97          // at the beginning of the next block.
98          if (!scratch->empty()) {
99            ReportCorruption(scratch->size(), "partial record without end(1)");
100          }
101        }
102        prospective_record_offset = physical_record_offset;
103        scratch->clear();
104        *record = fragment;
105        last_record_offset_ = prospective_record_offset;
106        return true;
107
108      case kFirstType:
109        if (in_fragmented_record) {
110          // Handle bug in earlier versions of log::Writer where
111          // it could emit an empty kFirstType record at the tail end
112          // of a block followed by a kFullType or kFirstType record
113          // at the beginning of the next block.
114          if (!scratch->empty()) {
115            ReportCorruption(scratch->size(), "partial record without end(2)");
116          }
117        }
118        prospective_record_offset = physical_record_offset;
119        scratch->assign(fragment.data(), fragment.size());
120        in_fragmented_record = true;
121        break;
122
123      case kMiddleType:
124        if (!in_fragmented_record) {
125          ReportCorruption(fragment.size(),
126                           "missing start of fragmented record(1)");
127        } else {
128          scratch->append(fragment.data(), fragment.size());
129        }
130        break;
131
132      case kLastType:
133        if (!in_fragmented_record) {
134          ReportCorruption(fragment.size(),
135                           "missing start of fragmented record(2)");
136        } else {
137          scratch->append(fragment.data(), fragment.size());
138          *record = Slice(*scratch);
139          last_record_offset_ = prospective_record_offset;
140          return true;
141        }
142        break;
143
144      case kEof:
145        if (in_fragmented_record) {
146          // This can be caused by the writer dying immediately after
147          // writing a physical record but before completing the next; don't
148          // treat it as a corruption, just ignore the entire logical record.
149          scratch->clear();
150        }
151        return false;
152
153      case kBadRecord:
154        if (in_fragmented_record) {
155          ReportCorruption(scratch->size(), "error in middle of record");
156          in_fragmented_record = false;
157          scratch->clear();
158        }
159        break;
160
161      default: {
162        char buf[40];
163        snprintf(buf, sizeof(buf), "unknown record type %u", record_type);
164        ReportCorruption(
165            (fragment.size() + (in_fragmented_record ? scratch->size() : 0)),
166            buf);
167        in_fragmented_record = false;
168        scratch->clear();
169        break;
170      }
171    }
172  }
173  return false;
174}
175
176uint64_t Reader::LastRecordOffset() { return last_record_offset_; }
177
178void Reader::ReportCorruption(uint64_t bytes, const char* reason) {
179  ReportDrop(bytes, Status::Corruption(reason, file_->GetName()));
180}
181
182void Reader::ReportDrop(uint64_t bytes, const Status& reason) {
183  if (reporter_ != nullptr &&
184      end_of_buffer_offset_ - buffer_.size() - bytes >= initial_offset_) {
185    reporter_->Corruption(static_cast<size_t>(bytes), reason);
186  }
187}
188
189unsigned int Reader::ReadPhysicalRecord(Slice* result) {
190  while (true) {
191    if (buffer_.size() < kHeaderSize) {
192      if (!eof_) {
193        // Last read was a full read, so this is a trailer to skip
194        buffer_.clear();
195        Status status = file_->Read(kBlockSize, &buffer_, backing_store_);
196        end_of_buffer_offset_ += buffer_.size();
197        if (!status.ok()) {
198          buffer_.clear();
199          ReportDrop(kBlockSize, status);
200          eof_ = true;
201          return kEof;
202        } else if (buffer_.size() < kBlockSize) {
203          eof_ = true;
204        }
205        continue;
206      } else {
207        // Note that if buffer_ is non-empty, we have a truncated header at the
208        // end of the file, which can be caused by the writer crashing in the
209        // middle of writing the header. Instead of considering this an error,
210        // just report EOF.
211        buffer_.clear();
212        return kEof;
213      }
214    }
215
216    // Parse the header
217    const char* header = buffer_.data();
218    const uint32_t a = static_cast<uint32_t>(header[4]) & 0xff;
219    const uint32_t b = static_cast<uint32_t>(header[5]) & 0xff;
220    const unsigned int type = header[6];
221    const uint32_t length = a | (b << 8);
222    if (kHeaderSize + length > buffer_.size()) {
223      size_t drop_size = buffer_.size();
224      buffer_.clear();
225      if (!eof_) {
226        ReportCorruption(drop_size, "bad record length");
227        return kBadRecord;
228      }
229      // If the end of the file has been reached without reading |length| bytes
230      // of payload, assume the writer died in the middle of writing the record.
231      // Don't report a corruption.
232      return kEof;
233    }
234
235    if (type == kZeroType && length == 0) {
236      // Skip zero length record without reporting any drops since
237      // such records are produced by the mmap based writing code in
238      // env_posix.cc that preallocates file regions.
239      buffer_.clear();
240      return kBadRecord;
241    }
242
243    // Check crc
244    if (checksum_) {
245      uint32_t expected_crc = crc32c::Unmask(DecodeFixed32(header));
246      uint32_t actual_crc = crc32c::Value(header + 6, 1 + length);
247      if (actual_crc != expected_crc) {
248        // Drop the rest of the buffer since "length" itself may have
249        // been corrupted and if we trust it, we could find some
250        // fragment of a real log record that just happens to look

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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