rocksdb/db/db_kv_checksum_test.cc
Andrew Kryczka 78ee8564ad Integrity protection for live updates to WriteBatch (#7748)
Summary:
This PR adds the foundation classes for key-value integrity protection and the first use case: protecting live updates from the source buffers added to `WriteBatch` through the destination buffer in `MemTable`. The width of the protection info is not yet configurable -- only eight bytes per key is supported. This PR allows users to enable protection by constructing `WriteBatch` with `protection_bytes_per_key == 8`. It does not yet expose a way for users to get integrity protection via other write APIs (e.g., `Put()`, `Merge()`, `Delete()`, etc.).

The foundation classes (`ProtectionInfo.*`) embed the coverage info in their type, and provide `Protect.*()` and `Strip.*()` functions to navigate between types with different coverage. For making bytes per key configurable (for powers of two up to eight) in the future, these classes are templated on the unsigned integer type used to store the protection info. That integer contains the XOR'd result of hashes with independent seeds for all covered fields. For integer fields, the hash is computed on the raw unadjusted bytes, so the result is endian-dependent. The most significant bytes are truncated when the hash value (8 bytes) is wider than the protection integer.

When `WriteBatch` is constructed with `protection_bytes_per_key == 8`, we hold a `ProtectionInfoKVOTC` (i.e., one that covers key, value, optype aka `ValueType`, timestamp, and CF ID) for each entry added to the batch. The protection info is generated from the original buffers passed by the user, as well as the original metadata generated internally. When writing to memtable, each entry is transformed to a `ProtectionInfoKVOTS` (i.e., dropping coverage of CF ID and adding coverage of sequence number), since at that point we know the sequence number, and have already selected a memtable corresponding to a particular CF. This protection info is verified once the entry is encoded in the `MemTable` buffer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7748

Test Plan:
- an integration test to verify a wide variety of single-byte changes to the encoded `MemTable` buffer are caught
- add to stress/crash test to verify it works in variety of configs/operations without intentional corruption
- [deferred] unit tests for `ProtectionInfo.*` classes for edge cases like KV swap, `SliceParts` and `Slice` APIs are interchangeable, etc.

Reviewed By: pdillinger

Differential Revision: D25754492

Pulled By: ajkr

fbshipit-source-id: e481bac6c03c2ab268be41359730f1ceb9964866
2021-01-29 12:18:58 -08:00

200 lines
6.8 KiB
C++

// Copyright (c) 2020-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include "db/db_test_util.h"
#include "rocksdb/rocksdb_namespace.h"
namespace ROCKSDB_NAMESPACE {
enum class WriteBatchOpType {
kPut = 0,
kDelete,
kSingleDelete,
kDeleteRange,
kMerge,
kBlobIndex,
kNum,
};
// Integer addition is needed for `::testing::Range()` to take the enum type.
WriteBatchOpType operator+(WriteBatchOpType lhs, const int rhs) {
using T = std::underlying_type<WriteBatchOpType>::type;
return static_cast<WriteBatchOpType>(static_cast<T>(lhs) + rhs);
}
class DbKvChecksumTest
: public DBTestBase,
public ::testing::WithParamInterface<std::tuple<WriteBatchOpType, char>> {
public:
DbKvChecksumTest()
: DBTestBase("/db_kv_checksum_test", /*env_do_fsync=*/false) {
op_type_ = std::get<0>(GetParam());
corrupt_byte_addend_ = std::get<1>(GetParam());
}
std::pair<WriteBatch, Status> GetWriteBatch(size_t ts_sz,
ColumnFamilyHandle* cf_handle) {
Status s;
WriteBatch wb(0 /* reserved_bytes */, 0 /* max_bytes */, ts_sz,
8 /* protection_bytes_per_entry */);
switch (op_type_) {
case WriteBatchOpType::kPut:
s = wb.Put(cf_handle, "key", "val");
break;
case WriteBatchOpType::kDelete:
s = wb.Delete(cf_handle, "key");
break;
case WriteBatchOpType::kSingleDelete:
s = wb.SingleDelete(cf_handle, "key");
break;
case WriteBatchOpType::kDeleteRange:
s = wb.DeleteRange(cf_handle, "begin", "end");
break;
case WriteBatchOpType::kMerge:
s = wb.Merge(cf_handle, "key", "val");
break;
case WriteBatchOpType::kBlobIndex:
// TODO(ajkr): use public API once available.
uint32_t cf_id;
if (cf_handle == nullptr) {
cf_id = 0;
} else {
cf_id = cf_handle->GetID();
}
s = WriteBatchInternal::PutBlobIndex(&wb, cf_id, "key", "val");
break;
case WriteBatchOpType::kNum:
assert(false);
}
return {std::move(wb), std::move(s)};
}
void CorruptNextByteCallBack(void* arg) {
Slice encoded = *static_cast<Slice*>(arg);
if (entry_len_ == port::kMaxSizet) {
// We learn the entry size on the first attempt
entry_len_ = encoded.size();
}
// All entries should be the same size
assert(entry_len_ == encoded.size());
char* buf = const_cast<char*>(encoded.data());
buf[corrupt_byte_offset_] += corrupt_byte_addend_;
++corrupt_byte_offset_;
}
bool MoreBytesToCorrupt() { return corrupt_byte_offset_ < entry_len_; }
protected:
WriteBatchOpType op_type_;
char corrupt_byte_addend_;
size_t corrupt_byte_offset_ = 0;
size_t entry_len_ = port::kMaxSizet;
};
std::string GetTestNameSuffix(
::testing::TestParamInfo<std::tuple<WriteBatchOpType, char>> info) {
std::ostringstream oss;
switch (std::get<0>(info.param)) {
case WriteBatchOpType::kPut:
oss << "Put";
break;
case WriteBatchOpType::kDelete:
oss << "Delete";
break;
case WriteBatchOpType::kSingleDelete:
oss << "SingleDelete";
break;
case WriteBatchOpType::kDeleteRange:
oss << "DeleteRange";
break;
case WriteBatchOpType::kMerge:
oss << "Merge";
break;
case WriteBatchOpType::kBlobIndex:
oss << "BlobIndex";
break;
case WriteBatchOpType::kNum:
assert(false);
}
oss << "Add"
<< static_cast<int>(static_cast<unsigned char>(std::get<1>(info.param)));
return oss.str();
}
INSTANTIATE_TEST_CASE_P(
DbKvChecksumTest, DbKvChecksumTest,
::testing::Combine(::testing::Range(static_cast<WriteBatchOpType>(0),
WriteBatchOpType::kNum),
::testing::Values(2, 103, 251)),
GetTestNameSuffix);
TEST_P(DbKvChecksumTest, MemTableAddCorrupted) {
// This test repeatedly attempts to write `WriteBatch`es containing a single
// entry of type `op_type_`. Each attempt has one byte corrupted in its
// memtable entry by adding `corrupt_byte_addend_` to its original value. The
// test repeats until an attempt has been made on each byte in the encoded
// memtable entry. All attempts are expected to fail with `Status::Corruption`
SyncPoint::GetInstance()->SetCallBack(
"MemTable::Add:Encoded",
std::bind(&DbKvChecksumTest::CorruptNextByteCallBack, this,
std::placeholders::_1));
while (MoreBytesToCorrupt()) {
// Failed memtable insert always leads to read-only mode, so we have to
// reopen for every attempt.
Options options = CurrentOptions();
if (op_type_ == WriteBatchOpType::kMerge) {
options.merge_operator = MergeOperators::CreateStringAppendOperator();
}
Reopen(options);
SyncPoint::GetInstance()->EnableProcessing();
auto batch_and_status =
GetWriteBatch(0 /* ts_sz */, nullptr /* cf_handle */);
ASSERT_OK(batch_and_status.second);
ASSERT_TRUE(
db_->Write(WriteOptions(), &batch_and_status.first).IsCorruption());
SyncPoint::GetInstance()->DisableProcessing();
}
}
TEST_P(DbKvChecksumTest, MemTableAddWithColumnFamilyCorrupted) {
// This test repeatedly attempts to write `WriteBatch`es containing a single
// entry of type `op_type_` to a non-default column family. Each attempt has
// one byte corrupted in its memtable entry by adding `corrupt_byte_addend_`
// to its original value. The test repeats until an attempt has been made on
// each byte in the encoded memtable entry. All attempts are expected to fail
// with `Status::Corruption`.
Options options = CurrentOptions();
if (op_type_ == WriteBatchOpType::kMerge) {
options.merge_operator = MergeOperators::CreateStringAppendOperator();
}
CreateAndReopenWithCF({"pikachu"}, options);
SyncPoint::GetInstance()->SetCallBack(
"MemTable::Add:Encoded",
std::bind(&DbKvChecksumTest::CorruptNextByteCallBack, this,
std::placeholders::_1));
while (MoreBytesToCorrupt()) {
// Failed memtable insert always leads to read-only mode, so we have to
// reopen for every attempt.
ReopenWithColumnFamilies({kDefaultColumnFamilyName, "pikachu"}, options);
SyncPoint::GetInstance()->EnableProcessing();
auto batch_and_status = GetWriteBatch(0 /* ts_sz */, handles_[1]);
ASSERT_OK(batch_and_status.second);
ASSERT_TRUE(
db_->Write(WriteOptions(), &batch_and_status.first).IsCorruption());
SyncPoint::GetInstance()->DisableProcessing();
}
}
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}