tdlight/tddb/td/db/binlog/BinlogEvent.cpp
Arseny Smirnov 9fd6ea8502 Validate binlog event just before a write
GitOrigin-RevId: cea03381299348b0c33af5f963ff24cb97f1e6e1
2018-07-09 13:48:22 +03:00

51 lines
1.8 KiB
C++

//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include "td/db/binlog/BinlogEvent.h"
#include "td/utils/tl_parsers.h"
namespace td {
int32 VERBOSITY_NAME(binlog) = VERBOSITY_NAME(DEBUG) + 8;
Status BinlogEvent::init(BufferSlice &&raw_event, bool check_crc) {
TlParser parser(raw_event.as_slice());
size_ = parser.fetch_int();
CHECK(size_ == raw_event.size()) << size_ << " " << raw_event.size() << debug_info_;
id_ = parser.fetch_long();
type_ = parser.fetch_int();
flags_ = parser.fetch_int();
extra_ = parser.fetch_long();
CHECK(size_ >= MIN_EVENT_SIZE);
auto slice_data = parser.fetch_string_raw<Slice>(size_ - MIN_EVENT_SIZE);
data_ = MutableSlice(const_cast<char *>(slice_data.begin()), slice_data.size());
crc32_ = static_cast<uint32>(parser.fetch_int());
if (check_crc) {
CHECK(size_ >= EVENT_TAIL_SIZE);
auto calculated_crc = crc32(raw_event.as_slice().truncate(size_ - EVENT_TAIL_SIZE));
if (calculated_crc != crc32_) {
return Status::Error(PSLICE() << "crc mismatch " << tag("actual", format::as_hex(calculated_crc))
<< tag("expected", format::as_hex(crc32_)) << public_to_string());
}
}
raw_event_ = std::move(raw_event);
return Status::OK();
}
Status BinlogEvent::validate() const {
BinlogEvent event;
if (raw_event_.size() < 4) {
return Status::Error("Too small event");
}
uint32 size = TlParser(raw_event_.as_slice().truncate(4)).fetch_int();
if (size_ != size) {
return Status::Error(PSLICE() << "Size of event changed: " << tag("was", size_) << tag("now", size));
}
return event.init(raw_event_.clone(), true);
}
} // namespace td