// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "chrome/browser/safe_browsing/safe_browsing_database.h"
#include "base/file_util.h"
#include "base/metrics/histogram.h"
#include "base/metrics/stats_counters.h"
#include "base/time.h"
#include "base/message_loop.h"
#include "base/process_util.h"
#include "base/sha2.h"
#include "chrome/browser/safe_browsing/bloom_filter.h"
#include "chrome/browser/safe_browsing/prefix_set.h"
#include "chrome/browser/safe_browsing/safe_browsing_store_file.h"
#include "googleurl/src/gurl.h"
namespace {
// Filename suffix for the bloom filter.
const FilePath::CharType kBloomFilterFile[] = FILE_PATH_LITERAL(" Filter 2");
// Filename suffix for download store.
const FilePath::CharType kDownloadDBFile[] = FILE_PATH_LITERAL(" Download");
// Filename suffix for browse store.
// TODO(lzheng): change to a better name when we change the file format.
const FilePath::CharType kBrowseDBFile[] = FILE_PATH_LITERAL(" Bloom");
// The maximum staleness for a cached entry.
const int kMaxStalenessMinutes = 45;
// To save space, the incoming |chunk_id| and |list_id| are combined
// into an |encoded_chunk_id| for storage by shifting the |list_id|
// into the low-order bits. These functions decode that information.
// TODO(lzheng): It was reasonable when database is saved in sqlite, but
// there should be better ways to save chunk_id and list_id after we use
// SafeBrowsingStoreFile.
int GetListIdBit(const int encoded_chunk_id) {
return encoded_chunk_id & 1;
}
int DecodeChunkId(int encoded_chunk_id) {
return encoded_chunk_id >> 1;
}
int EncodeChunkId(const int chunk, const int list_id) {
DCHECK_NE(list_id, safe_browsing_util::INVALID);
return chunk << 1 | list_id % 2;
}
// Get the prefix for download url.
void GetDownloadUrlPrefix(const GURL& url, SBPrefix* prefix) {
std::string hostname;
std::string path;
std::string query;
safe_browsing_util::CanonicalizeUrl(url, &hostname, &path, &query);
SBFullHash full_hash;
base::SHA256HashString(hostname + path + query, &full_hash,
sizeof(full_hash));
*prefix = full_hash.prefix;
}
// Generate the set of prefixes to check for |url|.
// TODO(shess): This function is almost the same as
// |CompareFullHashes()| in safe_browsing_util.cc, except that code
// does an early exit on match. Since match should be the infrequent
// case (phishing or malware found), consider combining this function
// with that one.
void BrowsePrefixesToCheck(const GURL& url, std::vector<SBPrefix>* prefixes) {
std::vector<std::string> hosts;
if (url.HostIsIPAddress()) {
hosts.push_back(url.host());
} else {
safe_browsing_util::GenerateHostsToCheck(url, &hosts);
}
std::vector<std::string> paths;
safe_browsing_util::GeneratePathsToCheck(url, &paths);
for (size_t i = 0; i < hosts.size(); ++i) {
for (size_t j = 0; j < paths.size(); ++j) {
SBFullHash full_hash;
base::SHA256HashString(hosts[i] + paths[j], &full_hash,
sizeof(full_hash));
prefixes->push_back(full_hash.prefix);
}
}
}
// Find the entries in |full_hashes| with prefix in |prefix_hits|, and
// add them to |full_hits| if not expired. "Not expired" is when
// either |last_update| was recent enough, or the item has been
// received recently enough. Expired items are not deleted because a
// future update may make them acceptable again.
//
// For efficiency reasons the code walks |prefix_hits| and
// |full_hashes| in parallel, so they must be sorted by prefix.
void GetCachedFullHashesForBrowse(const std::vector<SBPrefix>& prefix_hits,
const std::vector<SBAddFullHash>& full_hashes,
std::vector<SBFullHashResult>* full_hits,
base::Time last_update) {
const base::Time expire_time =
base::Time::Now() - base::TimeDelta::FromMinutes(kMaxStalenessMinutes);
std::vector<SBPrefix>::const_iterator piter = prefix_hits.begin();
std::vector<SBAddFullHash>::const_iterator hiter = full_hashes.begin();
while (piter != prefix_hits.end() && hiter != full_hashes.end()) {
if (*piter < hiter->full_hash.prefix) {
++piter;
} else if (hiter->full_hash.prefix < *piter) {
++hiter;
} else {
if (expire_time < last_update ||
expire_time.ToTimeT() < hiter->received) {
SBFullHashResult result;
const int list_bit = GetListIdBit(hiter->chunk_id);
DCHECK(list_bit == safe_browsing_util::MALWARE ||
list_bit == safe_browsing_util::PHISH);
if (!safe_browsing_util::GetListName(list_bit, &result.list_name))
continue;
result.add_chunk_id = DecodeChunkId(hiter->chunk_id);
result.hash = hiter->full_hash;
full_hits->push_back(result);
}
// Only increment |hiter|, |piter| might have multiple hits.
++hiter;
}
}
}
void GetChunkRanges(const std::vector<int>& chunks,
std::string* list0,
std::string* list1) {
std::vector<int> chunks0;
std::vector<int> chunks1;
for (std::vector<int>::const_iterator iter = chunks.begin();
iter != chunks.end(); ++iter) {
int mod_list_id = GetListIdBit(*iter);
if (0 == mod_list_id) {
chunks0.push_back(DecodeChunkId(*iter));
} else {
DCHECK_EQ(1, mod_list_id);
chunks1.push_back(DecodeChunkId(*iter));
}
}
ChunksToRangeString(chunks0, list0);
ChunksToRangeString(chunks1, list1);
}
// Helper function to create chunk range lists for Browse related
// lists.
void UpdateChunkRanges(const std::vector<int>& add_chunks,
const std::vector<int>& sub_chunks,
const std::string& list_name0,
const std::string& list_name1,
std::vector<SBListChunkRanges>* lists) {
DCHECK_EQ(safe_browsing_util::GetListId(list_name0) % 2, 0);
DCHECK_EQ(safe_browsing_util::GetListId(list_name1) % 2, 1);
DCHECK_NE(safe_browsing_util::GetListId(list_name0),
safe_browsing_util::INVALID);
DCHECK_NE(safe_browsing_util::GetListId(list_name1),
safe_browsing_util::INVALID);
SBListChunkRanges chunkrange0(list_name0);
SBListChunkRanges chunkrange1(list_name1);
GetChunkRanges(add_chunks, &chunkrange0.adds, &chunkrange1.adds);
GetChunkRanges(sub_chunks, &chunkrange0.subs, &chunkrange1.subs);
lists->push_back(chunkrange0);
lists->push_back(chunkrange1);
}
// Order |SBAddFullHash| on the prefix part. |SBAddPrefixLess()| from
// safe_browsing_store.h orders on both chunk-id and prefix.
bool SBAddFullHashPrefixLess(const SBAddFullHash& a, const SBAddFullHash& b) {
return a.full_hash.prefix < b.full_hash.prefix;
}
// Create a |PrefixSet| from a vector of add-prefixes.
safe_browsing::PrefixSet* CreatePrefixSet(
const std::vector<SBAddPrefix>& add_prefixes) {
std::vector<SBPrefix> prefixes;
for (size_t i = 0; i < add_prefixes.size(); ++i) {
prefixes.push_back(add_prefixes[i].prefix);
}
return new safe_browsing::PrefixSet(prefixes);
}
// As compared to the bloom filter, PrefixSet should have these
// properties:
// - Any bloom filter miss should be a prefix set miss.
// - Any prefix set hit should be a bloom filter hit.
// - Bloom filter false positives are prefix set misses.
// The following is to log actual performance to verify this.
enum PrefixSetEvent {
PREFIX_SET_EVENT_HIT,
PREFIX_SET_EVENT_BLOOM_HIT,
PREFIX_SET_EVENT_BLOOM_MISS_PREFIX_HIT,
// Memory space for histograms is determined by the max. ALWAYS ADD
// NEW VALUES BEFORE THIS ONE.
PREFIX_SET_EVENT_MAX
};
void RecordPrefixSetInfo(PrefixSetEvent event_type) {
UMA_HISTOGRAM_ENUMERATION("SB2.PrefixSetEvent", event_type,
PREFIX_SET_EVENT_MAX);
}
} // namespace
// The default SafeBrowsingDatabaseFactory.
class SafeBrowsingDatabaseFactoryImpl : public SafeBrowsingDatabaseFactory {
public:
virtual SafeBrowsingDatabase* CreateSafeBrowsingDatabase(
bool enable_download_protection) {
if (enable_download_protection) {
// Create database with browse url store and download store.
return new SafeBrowsingDatabaseNew(new SafeBrowsingStoreFile,
new SafeBrowsingStoreFile);
}
// Create database with only browse url store.
return new SafeBrowsingDatabaseNew(new SafeBrowsingStoreFile, NULL);
}
SafeBrowsingDatabaseFactoryImpl() { }
private:
DISALLOW_COPY_AND_ASSIGN(SafeBrowsingDatabaseFactoryImpl);
};
// static
SafeBrowsingDatabaseFactory* SafeBrowsingDatabase::factory_ = NULL;
// Factory method, non-thread safe. Caller has to make sure this s called
// on SafeBrowsing Thread.
// TODO(shess): There's no need for a factory any longer. Convert
// SafeBrowsingDatabaseNew to SafeBrowsingDatabase, and have Create()
// callers just construct things directly.
SafeBrowsingDatabase* SafeBrowsingDatabase::Create(
bool enable_download_protection) {
if (!factory_)
factory_ = new SafeBrowsingDatabaseFactoryImpl();
return factory_->CreateSafeBrowsingDatabase(enable_download_protection);
}
SafeBrowsingDatabase::~SafeBrowsingDatabase() {
}
// static
FilePath SafeBrowsingDatabase::BrowseDBFilename(
const FilePath& db_base_filename) {
return FilePath(db_base_filename.value() + kBrowseDBFile);
}
// static
FilePath SafeBrowsingDatabase::DownloadDBFilename(
const FilePath& db_base_filename) {
return FilePath(db_base_filename.value() + kDownloadDBFile);
}
// static
FilePath SafeBrowsingDatabase::BloomFilterForFilename(
const FilePath& db_filename) {
return FilePath(db_filename.value() + kBloomFilterFile);
}
SafeBrowsingStore* SafeBrowsingDatabaseNew::GetStore(const int list_id) {
DVLOG(3) << "Get store for list: " << list_id;
if (list_id == safe_browsing_util::PHISH ||
list_id == safe_browsing_util::MALWARE) {
return browse_store_.get();
} else if (list_id == safe_browsing_util::BINURL ||
list_id == safe_browsing_util::BINHASH) {
return download_store_.get();
}
return NULL;
}
// static
void SafeBrowsingDatabase::RecordFailure(FailureType failure_type) {
UMA_HISTOGRAM_ENUMERATION("SB2.DatabaseFailure", failure_type,
FAILURE_DATABASE_MAX);
}
SafeBrowsingDatabaseNew::SafeBrowsingDatabaseNew()
: creation_loop_(MessageLoop::current()),
browse_store_(new SafeBrowsingStoreFile),
download_store_(NULL),
ALLOW_THIS_IN_INITIALIZER_LIST(reset_factory_(this)) {
DCHECK(browse_store_.get());
DCHECK(!download_store_.get());
}
SafeBrowsingDatabaseNew::SafeBrowsingDatabaseNew(
SafeBrowsingStore* browse_store, SafeBrowsingStore* download_store)
: creation_loop_(MessageLoop::current()),
browse_store_(browse_store),
download_store_(download_store),
ALLOW_THIS_IN_INITIALIZER_LIST(reset_factory_(this)),
corruption_detected_(false) {
DCHECK(browse_store_.get());
}
SafeBrowsingDatabaseNew::~SafeBrowsingDatabaseNew() {
DCHECK_EQ(creation_loop_, MessageLoop::current());
}
void SafeBrowsingDatabaseNew::Init(const FilePath& filename_base) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
// NOTE: There is no need to grab the lock in this function, since
// until it returns, there are no pointers to this class on other
// threads. Then again, that means there is no possibility of
// contention on the lock...
base::AutoLock locked(lookup_lock_);
DCHECK(browse_filename_.empty()); // Ensure we haven't been run before.
DCHECK(download_filename_.empty()); // Ensure we haven't been run before.
browse_filename_ = BrowseDBFilename(filename_base);
browse_store_->Init(
browse_filename_,
NewCallback(this, &SafeBrowsingDatabaseNew::HandleCorruptDatabase));
full_browse_hashes_.clear();
pending_browse_hashes_.clear();
bloom_filter_filename_ = BloomFilterForFilename(browse_filename_);
LoadBloomFilter();
DVLOG(1) << "Init browse store: " << browse_filename_.value();
if (download_store_.get()) {
download_filename_ = DownloadDBFilename(filename_base);
download_store_->Init(
download_filename_,
NewCallback(this, &SafeBrowsingDatabaseNew::HandleCorruptDatabase));
DVLOG(1) << "Init download store: " << download_filename_.value();
}
}
bool SafeBrowsingDatabaseNew::ResetDatabase() {
DCHECK_EQ(creation_loop_, MessageLoop::current());
// Delete files on disk.
// TODO(shess): Hard to see where one might want to delete without a
// reset. Perhaps inline |Delete()|?
if (!Delete())
return false;
// Reset objects in memory.
{
base::AutoLock locked(lookup_lock_);
full_browse_hashes_.clear();
pending_browse_hashes_.clear();
prefix_miss_cache_.clear();
// TODO(shess): This could probably be |bloom_filter_.reset()|.
browse_bloom_filter_ = new BloomFilter(BloomFilter::kBloomFilterMinSize *
BloomFilter::kBloomFilterSizeRatio);
// TODO(shess): It is simpler for the code to assume that presence
// of a bloom filter always implies presence of a prefix set.
prefix_set_.reset(CreatePrefixSet(std::vector<SBAddPrefix>()));
}
return true;
}
// TODO(lzheng): Remove matching_list, it is not used anywhere.
bool SafeBrowsingDatabaseNew::ContainsBrowseUrl(
const GURL& url,
std::string* matching_list,
std::vector<SBPrefix>* prefix_hits,
std::vector<SBFullHashResult>* full_hits,
base::Time last_update) {
// Clear the results first.
matching_list->clear();
prefix_hits->clear();
full_hits->clear();
std::vector<SBPrefix> prefixes;
BrowsePrefixesToCheck(url, &prefixes);
if (prefixes.empty())
return false;
// This function is called on the I/O thread, prevent changes to
// bloom filter and caches.
base::AutoLock locked(lookup_lock_);
if (!browse_bloom_filter_.get())
return false;
DCHECK(prefix_set_.get());
size_t miss_count = 0;
for (size_t i = 0; i < prefixes.size(); ++i) {
bool found = prefix_set_->Exists(prefixes[i]);
if (browse_bloom_filter_->Exists(prefixes[i])) {
RecordPrefixSetInfo(PREFIX_SET_EVENT_BLOOM_HIT);
if (found)
RecordPrefixSetInfo(PREFIX_SET_EVENT_HIT);
prefix_hits->push_back(prefixes[i]);
if (prefix_miss_cache_.count(prefixes[i]) > 0)
++miss_count;
} else {
// Bloom filter misses should never be in prefix set.
DCHECK(!found);
if (found)
RecordPrefixSetInfo(PREFIX_SET_EVENT_BLOOM_MISS_PREFIX_HIT);
}
}
// If all the prefixes are cached as 'misses', don't issue a GetHash.
if (miss_count == prefix_hits->size())
return false;
// Find the matching full-hash results. |full_browse_hashes_| are from the
// database, |pending_browse_hashes_| are from GetHash requests between
// updates.
std::sort(prefix_hits->begin(), prefix_hits->end());
GetCachedFullHashesForBrowse(*prefix_hits, full_browse_hashes_,
full_hits, last_update);
GetCachedFullHashesForBrowse(*prefix_hits, pending_browse_hashes_,
full_hits, last_update);
return true;
}
bool SafeBrowsingDatabaseNew::MatchDownloadAddPrefixes(
int list_bit, const SBPrefix& prefix, SBPrefix* prefix_hit) {
std::vector<SBAddPrefix> add_prefixes;
download_store_->GetAddPrefixes(&add_prefixes);
for (size_t i = 0; i < add_prefixes.size(); ++i) {
if (prefix == add_prefixes[i].prefix &&
GetListIdBit(add_prefixes[i].chunk_id) == list_bit) {
*prefix_hit = prefix;
return true;
}
}
return false;
}
bool SafeBrowsingDatabaseNew::ContainsDownloadUrl(const GURL& url,
SBPrefix* prefix_hit) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
// Ignore this check when download checking is not enabled.
if (!download_store_.get())
return false;
SBPrefix prefix;
GetDownloadUrlPrefix(url, &prefix);
return MatchDownloadAddPrefixes(safe_browsing_util::BINURL % 2,
prefix,
prefix_hit);
}
bool SafeBrowsingDatabaseNew::ContainsDownloadHashPrefix(
const SBPrefix& prefix) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
// Ignore this check when download store is not available.
if (!download_store_.get())
return false;
SBPrefix prefix_hit;
return MatchDownloadAddPrefixes(safe_browsing_util::BINHASH % 2,
prefix,
&prefix_hit);
}
// Helper to insert entries for all of the prefixes or full hashes in
// |entry| into the store.
void SafeBrowsingDatabaseNew::InsertAdd(int chunk_id, SBPrefix host,
const SBEntry* entry, int list_id) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
SafeBrowsingStore* store = GetStore(list_id);
if (!store) return;
STATS_COUNTER("SB.HostInsert", 1);
const int encoded_chunk_id = EncodeChunkId(chunk_id, list_id);
const int count = entry->prefix_count();
DCHECK(!entry->IsSub());
if (!count) {
// No prefixes, use host instead.
STATS_COUNTER("SB.PrefixAdd", 1);
store->WriteAddPrefix(encoded_chunk_id, host);
} else if (entry->IsPrefix()) {
// Prefixes only.
for (int i = 0; i < count; i++) {
const SBPrefix prefix = entry->PrefixAt(i);
STATS_COUNTER("SB.PrefixAdd", 1);
store->WriteAddPrefix(encoded_chunk_id, prefix);
}
} else {
// Prefixes and hashes.
const base::Time receive_time = base::Time::Now();
for (int i = 0; i < count; ++i) {
const SBFullHash full_hash = entry->FullHashAt(i);
const SBPrefix prefix = full_hash.prefix;
STATS_COUNTER("SB.PrefixAdd", 1);
store->WriteAddPrefix(encoded_chunk_id, prefix);
STATS_COUNTER("SB.PrefixAddFull", 1);
store->WriteAddHash(encoded_chunk_id, receive_time, full_hash);
}
}
}
// Helper to iterate over all the entries in the hosts in |chunks| and
// add them to the store.
void SafeBrowsingDatabaseNew::InsertAddChunks(const int list_id,
const SBChunkList& chunks) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
SafeBrowsingStore* store = GetStore(list_id);
if (!store) return;
for (SBChunkList::const_iterator citer = chunks.begin();
citer != chunks.end(); ++citer) {
const int chunk_id = citer->chunk_number;
// The server can give us a chunk that we already have because
// it's part of a range. Don't add it again.
const int encoded_chunk_id = EncodeChunkId(chunk_id, list_id);
if (store->CheckAddChunk(encoded_chunk_id))
continue;
store->SetAddChunk(encoded_chunk_id);
for (std::deque<SBChunkHost>::const_iterator hiter = citer->hosts.begin();
hiter != citer->hosts.end(); ++hiter) {
// NOTE: Could pass |encoded_chunk_id|, but then inserting add
// chunks would look different from inserting sub chunks.
InsertAdd(chunk_id, hiter->host, hiter->entry, list_id);
}
}
}
// Helper to insert entries for all of the prefixes or full hashes in
// |entry| into the store.
void SafeBrowsingDatabaseNew::InsertSub(int chunk_id, SBPrefix host,
const SBEntry* entry, int list_id) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
SafeBrowsingStore* store = GetStore(list_id);
if (!store) return;
STATS_COUNTER("SB.HostDelete", 1);
const int encoded_chunk_id = EncodeChunkId(chunk_id, list_id);
const int count = entry->prefix_count();
DCHECK(entry->IsSub());
if (!count) {
// No prefixes, use host instead.
STATS_COUNTER("SB.PrefixSub", 1);
const int add_chunk_id = EncodeChunkId(entry->chunk_id(), list_id);
store->WriteSubPrefix(encoded_chunk_id, add_chunk_id, host);
} else if (entry->IsPrefix()) {
// Prefixes only.
for (int i = 0; i < count; i++) {
const SBPrefix prefix = entry->PrefixAt(i);
const int add_chunk_id =
EncodeChunkId(entry->ChunkIdAtPrefix(i), list_id);
STATS_COUNTER("SB.PrefixSub", 1);
store->WriteSubPrefix(encoded_chunk_id, add_chunk_id, prefix);
}
} else {
// Prefixes and hashes.
for (int i = 0; i < count; ++i) {
const SBFullHash full_hash = entry->FullHashAt(i);
const int add_chunk_id =
EncodeChunkId(entry->ChunkIdAtPrefix(i), list_id);
STATS_COUNTER("SB.PrefixSub", 1);
store->WriteSubPrefix(encoded_chunk_id, add_chunk_id, full_hash.prefix);
STATS_COUNTER("SB.PrefixSubFull", 1);
store->WriteSubHash(encoded_chunk_id, add_chunk_id, full_hash);
}
}
}
// Helper to iterate over all the entries in the hosts in |chunks| and
// add them to the store.
void SafeBrowsingDatabaseNew::InsertSubChunks(int list_id,
const SBChunkList& chunks) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
SafeBrowsingStore* store = GetStore(list_id);
if (!store) return;
for (SBChunkList::const_iterator citer = chunks.begin();
citer != chunks.end(); ++citer) {
const int chunk_id = citer->chunk_number;
// The server can give us a chunk that we already have because
// it's part of a range. Don't add it again.
const int encoded_chunk_id = EncodeChunkId(chunk_id, list_id);
if (store->CheckSubChunk(encoded_chunk_id))
continue;
store->SetSubChunk(encoded_chunk_id);
for (std::deque<SBChunkHost>::const_iterator hiter = citer->hosts.begin();
hiter != citer->hosts.end(); ++hiter) {
InsertSub(chunk_id, hiter->host, hiter->entry, list_id);
}
}
}
void SafeBrowsingDatabaseNew::InsertChunks(const std::string& list_name,
const SBChunkList& chunks) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
if (corruption_detected_ || chunks.empty())
return;
const base::Time insert_start = base::Time::Now();
const int list_id = safe_browsing_util::GetListId(list_name);
DVLOG(2) << list_name << ": " << list_id;
SafeBrowsingStore* store = GetStore(list_id);
if (!store) return;
change_detected_ = true;
store->BeginChunk();
if (chunks.front().is_add) {
InsertAddChunks(list_id, chunks);
} else {
InsertSubChunks(list_id, chunks);
}
store->FinishChunk();
UMA_HISTOGRAM_TIMES("SB2.ChunkInsert", base::Time::Now() - insert_start);
}
void SafeBrowsingDatabaseNew::DeleteChunks(
const std::vector<SBChunkDelete>& chunk_deletes) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
if (corruption_detected_ || chunk_deletes.empty())
return;
const std::string& list_name = chunk_deletes.front().list_name;
const int list_id = safe_browsing_util::GetListId(list_name);
SafeBrowsingStore* store = GetStore(list_id);
if (!store) return;
change_detected_ = true;
for (size_t i = 0; i < chunk_deletes.size(); ++i) {
std::vector<int> chunk_numbers;
RangesToChunks(chunk_deletes[i].chunk_del, &chunk_numbers);
for (size_t j = 0; j < chunk_numbers.size(); ++j) {
const int encoded_chunk_id = EncodeChunkId(chunk_numbers[j], list_id);
if (chunk_deletes[i].is_sub_del)
store->DeleteSubChunk(encoded_chunk_id);
else
store->DeleteAddChunk(encoded_chunk_id);
}
}
}
void SafeBrowsingDatabaseNew::CacheHashResults(
const std::vector<SBPrefix>& prefixes,
const std::vector<SBFullHashResult>& full_hits) {
// This is called on the I/O thread, lock against updates.
base::AutoLock locked(lookup_lock_);
if (full_hits.empty()) {
prefix_miss_cache_.insert(prefixes.begin(), prefixes.end());
return;
}
// TODO(shess): SBFullHashResult and SBAddFullHash are very similar.
// Refactor to make them identical.
const base::Time now = base::Time::Now();
const size_t orig_size = pending_browse_hashes_.size();
for (std::vector<SBFullHashResult>::const_iterator iter = full_hits.begin();
iter != full_hits.end(); ++iter) {
const int list_id = safe_browsing_util::GetListId(iter->list_name);
if (list_id == safe_browsing_util::MALWARE ||
list_id == safe_browsing_util::PHISH) {
int encoded_chunk_id = EncodeChunkId(iter->add_chunk_id, list_id);
SBAddFullHash add_full_hash(encoded_chunk_id, now, iter->hash);
pending_browse_hashes_.push_back(add_full_hash);
}
}
// Sort new entries then merge with the previously-sorted entries.
std::vector<SBAddFullHash>::iterator
orig_end = pending_browse_hashes_.begin() + orig_size;
std::sort(orig_end, pending_browse_hashes_.end(), SBAddFullHashPrefixLess);
std::inplace_merge(pending_browse_hashes_.begin(),
orig_end, pending_browse_hashes_.end(),
SBAddFullHashPrefixLess);
}
bool SafeBrowsingDatabaseNew::UpdateStarted(
std::vector<SBListChunkRanges>* lists) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
DCHECK(lists);
// If |BeginUpdate()| fails, reset the database.
if (!browse_store_->BeginUpdate()) {
RecordFailure(FAILURE_BROWSE_DATABASE_UPDATE_BEGIN);
HandleCorruptDatabase();
return false;
}
if (download_store_.get() && !download_store_->BeginUpdate()) {
RecordFailure(FAILURE_DOWNLOAD_DATABASE_UPDATE_BEGIN);
HandleCorruptDatabase();
return false;
}
std::vector<int> browse_add_chunks;
browse_store_->GetAddChunks(&browse_add_chunks);
std::vector<int> browse_sub_chunks;
browse_store_->GetSubChunks(&browse_sub_chunks);
UpdateChunkRanges(browse_add_chunks, browse_sub_chunks,
safe_browsing_util::kMalwareList,
safe_browsing_util::kPhishingList,
lists);
if (download_store_.get()) {
std::vector<int> download_add_chunks;
download_store_->GetAddChunks(&download_add_chunks);
std::vector<int> download_sub_chunks;
download_store_->GetSubChunks(&download_sub_chunks);
UpdateChunkRanges(download_add_chunks, download_sub_chunks,
safe_browsing_util::kBinUrlList,
safe_browsing_util::kBinHashList,
lists);
}
corruption_detected_ = false;
change_detected_ = false;
return true;
}
void SafeBrowsingDatabaseNew::UpdateFinished(bool update_succeeded) {
DCHECK_EQ(creation_loop_, MessageLoop::current());
if (corruption_detected_)
return;
// Unroll the transaction if there was a protocol error or if the
// transaction was empty. This will leave the bloom filter, the
// pending hashes, and the prefix miss cache in place.
if (!update_succeeded || !change_detected_) {
// Track empty updates to answer questions at http://crbug.com/72216 .
if (update_succeeded && !change_detected_)
UMA_HISTOGRAM_COUNTS("SB2.DatabaseUpdateKilobytes", 0);
browse_store_->CancelUpdate();
if (download_store_.get())
download_store_->CancelUpdate();
return;
}
// for download
UpdateDownloadStore();
// for browsing
UpdateBrowseStore();
}
void SafeBrowsingDatabaseNew:: UpdateDownloadStore() {
if (!download_store_.get())
return;
// For download, we don't cache and save full hashes.
std::vector<SBAddFullHash> empty_add_hashes;
// For download, backend lookup happens only if a prefix is in add list.
// No need to pass in miss cache when call FinishUpdate to caculate
// bloomfilter false positives.
std::set<SBPrefix> empty_miss_cache;
// These results are not used after this call. Simply ignore the
// returned value after FinishUpdate(...).
std::vector<SBAddPrefix> add_prefixes_result;
std::vector<SBAddFullHash> add_full_hashes_result;
if (!download_store_->FinishUpdate(empty_add_hashes,
empty_miss_cache,
&add_prefixes_result,
&add_full_hashes_result))
RecordFailure(FAILURE_DOWNLOAD_DATABASE_UPDATE_FINISH);
return;
}
void SafeBrowsingDatabaseNew::UpdateBrowseStore() {
// Copy out the pending add hashes. Copy rather than swapping in
// case |ContainsBrowseURL()| is called before the new filter is complete.
std::vector<SBAddFullHash> pending_add_hashes;
{
base::AutoLock locked(lookup_lock_);
pending_add_hashes.insert(pending_add_hashes.end(),
pending_browse_hashes_.begin(),
pending_browse_hashes_.end());
}
// Measure the amount of IO during the bloom filter build.
base::IoCounters io_before, io_after;
base::ProcessHandle handle = base::Process::Current().handle();
scoped_ptr<base::ProcessMetrics> metric(
#if !defined(OS_MACOSX)
base::ProcessMetrics::CreateProcessMetrics(handle)
#else
// Getting stats only for the current process is enough, so NULL is fine.
base::ProcessMetrics::CreateProcessMetrics(handle, NULL)
#endif
);
// IoCounters are currently not supported on Mac, and may not be
// available for Linux, so we check the result and only show IO
// stats if they are available.
const bool got_counters = metric->GetIOCounters(&io_before);
const base::Time before = base::Time::Now();
std::vector<SBAddPrefix> add_prefixes;
std::vector<SBAddFullHash> add_full_hashes;
if (!browse_store_->FinishUpdate(pending_add_hashes, prefix_miss_cache_,
&add_prefixes, &add_full_hashes)) {
RecordFailure(FAILURE_BROWSE_DATABASE_UPDATE_FINISH);
return;
}
// Create and populate |filter| from |add_prefixes|.
// TODO(shess): The bloom filter doesn't need to be a
// scoped_refptr<> for this code. Refactor that away.
const int filter_size =
BloomFilter::FilterSizeForKeyCount(add_prefixes.size());
scoped_refptr<BloomFilter> filter(new BloomFilter(filter_size));
for (size_t i = 0; i < add_prefixes.size(); ++i) {
filter->Insert(add_prefixes[i].prefix);
}
scoped_ptr<safe_browsing::PrefixSet>
prefix_set(CreatePrefixSet(add_prefixes));
// This needs to be in sorted order by prefix for efficient access.
std::sort(add_full_hashes.begin(), add_full_hashes.end(),
SBAddFullHashPrefixLess);
// Swap in the newly built filter and cache.
{
base::AutoLock locked(lookup_lock_);
full_browse_hashes_.swap(add_full_hashes);
// TODO(shess): If |CacheHashResults()| is posted between the
// earlier lock and this clear, those pending hashes will be lost.
// It could be fixed by only removing hashes which were collected
// at the earlier point. I believe that is fail-safe as-is (the
// hash will be fetched again).
pending_browse_hashes_.clear();
prefix_miss_cache_.clear();
browse_bloom_filter_.swap(filter);
prefix_set_.swap(prefix_set);
}
const base::TimeDelta bloom_gen = base::Time::Now() - before;
// Persist the bloom filter to disk. Since only this thread changes
// |browse_bloom_filter_|, there is no need to lock.
WriteBloomFilter();
// Gather statistics.
if (got_counters && metric->GetIOCounters(&io_after)) {
UMA_HISTOGRAM_COUNTS("SB2.BuildReadKilobytes",
static_cast<int>(io_after.ReadTransferCount -
io_before.ReadTransferCount) / 1024);
UMA_HISTOGRAM_COUNTS("SB2.BuildWriteKilobytes",
static_cast<int>(io_after.WriteTransferCount -
io_before.WriteTransferCount) / 1024);
UMA_HISTOGRAM_COUNTS("SB2.BuildReadOperations",
static_cast<int>(io_after.ReadOperationCount -
io_before.ReadOperationCount));
UMA_HISTOGRAM_COUNTS("SB2.BuildWriteOperations",
static_cast<int>(io_after.WriteOperationCount -
io_before.WriteOperationCount));
}
DVLOG(1) << "SafeBrowsingDatabaseImpl built bloom filter in "
<< bloom_gen.InMilliseconds() << " ms total. prefix count: "
<< add_prefixes.size();
UMA_HISTOGRAM_LONG_TIMES("SB2.BuildFilter", bloom_gen);
UMA_HISTOGRAM_COUNTS("SB2.FilterKilobytes",
browse_bloom_filter_->size() / 1024);
int64 size_64;
if (file_util::GetFileSize(browse_filename_, &size_64))
UMA_HISTOGRAM_COUNTS("SB2.BrowseDatabaseKilobytes",
static_cast<int>(size_64 / 1024));
if (file_util::GetFileSize(download_filename_, &size_64))
UMA_HISTOGRAM_COUNTS("SB2.DownloadDatabaseKilobytes",
static_cast<int>(size_64 / 1024));
}
void SafeBrowsingDatabaseNew::HandleCorruptDatabase() {
// Reset the database after the current task has unwound (but only
// reset once within the scope of a given task).
if (reset_factory_.empty()) {
RecordFailure(FAILURE_DATABASE_CORRUPT);
MessageLoop::current()->PostTask(FROM_HERE,
reset_factory_.NewRunnableMethod(
&SafeBrowsingDatabaseNew::OnHandleCorruptDatabase));
}
}
void SafeBrowsingDatabaseNew::OnHandleCorruptDatabase() {
RecordFailure(FAILURE_DATABASE_CORRUPT_HANDLER);
corruption_detected_ = true; // Stop updating the database.
ResetDatabase();
DCHECK(false) << "SafeBrowsing database was corrupt and reset";
}
// TODO(shess): I'm not clear why this code doesn't have any
// real error-handling.
void SafeBrowsingDatabaseNew::LoadBloomFilter() {
DCHECK_EQ(creation_loop_, MessageLoop::current());
DCHECK(!bloom_filter_filename_.empty());
// If we're missing either of the database or filter files, we wait until the
// next update to generate a new filter.
// TODO(paulg): Investigate how often the filter file is missing and how
// expensive it would be to regenerate it.
int64 size_64;
if (!file_util::GetFileSize(browse_filename_, &size_64) || size_64 == 0)
return;
if (!file_util::GetFileSize(bloom_filter_filename_, &size_64) ||
size_64 == 0) {
RecordFailure(FAILURE_DATABASE_FILTER_MISSING);
return;
}
const base::TimeTicks before = base::TimeTicks::Now();
browse_bloom_filter_ = BloomFilter::LoadFile(bloom_filter_filename_);
DVLOG(1) << "SafeBrowsingDatabaseNew read bloom filter in "
<< (base::TimeTicks::Now() - before).InMilliseconds() << " ms";
if (!browse_bloom_filter_.get())
RecordFailure(FAILURE_DATABASE_FILTER_READ);
// Manually re-generate the prefix set from the main database.
// TODO(shess): Write/read for prefix set.
std::vector<SBAddPrefix> add_prefixes;
browse_store_->GetAddPrefixes(&add_prefixes);
prefix_set_.reset(CreatePrefixSet(add_prefixes));
}
bool SafeBrowsingDatabaseNew::Delete() {
DCHECK_EQ(creation_loop_, MessageLoop::current());
const bool r1 = browse_store_->Delete();
if (!r1)
RecordFailure(FAILURE_DATABASE_STORE_DELETE);
const bool r2 = download_store_.get() ? download_store_->Delete() : true;
if (!r2)
RecordFailure(FAILURE_DATABASE_STORE_DELETE);
const bool r3 = file_util::Delete(bloom_filter_filename_, false);
if (!r3)
RecordFailure(FAILURE_DATABASE_FILTER_DELETE);
return r1 && r2 && r3;
}
void SafeBrowsingDatabaseNew::WriteBloomFilter() {
DCHECK_EQ(creation_loop_, MessageLoop::current());
if (!browse_bloom_filter_.get())
return;
const base::TimeTicks before = base::TimeTicks::Now();
const bool write_ok = browse_bloom_filter_->WriteFile(bloom_filter_filename_);
DVLOG(1) << "SafeBrowsingDatabaseNew wrote bloom filter in "
<< (base::TimeTicks::Now() - before).InMilliseconds() << " ms";
if (!write_ok)
RecordFailure(FAILURE_DATABASE_FILTER_WRITE);
}