blob: 20f706ab592b287b1085e4ff7e4f7e0fad81339e [file] [log] [blame]
// Copyright 2016 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 <stddef.h>
#include <stdint.h>
#include "base/macros.h"
#include "base/numerics/safe_conversions.h"
#include "components/subresource_filter/core/common/flat/indexed_ruleset_generated.h"
#include "components/url_pattern_index/url_pattern_index.h"
#include "third_party/flatbuffers/src/include/flatbuffers/flatbuffers.h"
class GURL;
namespace url {
class Origin;
namespace url_pattern_index {
namespace proto {
class UrlRule;
namespace subresource_filter {
class FirstPartyOrigin;
// Detailed result of IndexedRulesetMatcher::Verify.
// Note: Logged to UMA, keep in sync with SubresourceFilterVerifyStatus in
// enums.xml. Add new entries to the end and do not renumber.
enum class VerifyStatus {
kPassValidChecksum = 0,
kChecksumFailVerifierPass = 1,
kChecksumFailVerifierFail = 2,
kVerifierFailChecksumPass = 3,
kVerifierFailChecksumZero = 4,
kPassChecksumZero = 5,
kMaxValue = kPassChecksumZero
// The class used to construct flat data structures representing the set of URL
// filtering rules, as well as the index of those. Internally owns a
// FlatBufferBuilder storing the structures.
class RulesetIndexer {
// The current binary format version of the indexed ruleset.
// Increase this value when introducing an incompatible change in
// IndexedRuleset format, or otherwise willing to nudge clients to rebuild
// their ruleset (e.g., a change is compatible, but significantly reduces the
// size of the buffer). Note: The script tries to keep
// contributors aware of that.
static const int kIndexedFormatVersion;
// Adds |rule| to the ruleset and the index unless the |rule| has unsupported
// filter options, in which case the data structures remain unmodified.
// Returns whether the |rule| has been serialized and added to the index.
bool AddUrlRule(const url_pattern_index::proto::UrlRule& rule);
// Finalizes construction of the data structures.
void Finish();
// Returns the checksum for the data buffer.
int GetChecksum() const;
// Returns a pointer to the buffer containing the serialized flat data
// structures. Should only be called after Finish().
const uint8_t* data() const { return builder_.GetBufferPointer(); }
// Returns the size of the buffer.
size_t size() const { return base::strict_cast<size_t>(builder_.GetSize()); }
flatbuffers::FlatBufferBuilder builder_;
url_pattern_index::UrlPatternIndexBuilder blacklist_;
url_pattern_index::UrlPatternIndexBuilder whitelist_;
url_pattern_index::UrlPatternIndexBuilder deactivation_;
// Maintains a map of domain vectors to their existing offsets, to avoid
// storing a particular vector more than once.
url_pattern_index::FlatDomainMap domain_map_;
// Matches URLs against the FlatBuffer representation of an indexed ruleset.
class IndexedRulesetMatcher {
// Returns whether the |buffer| of the given |size| contains a valid
// flat::IndexedRuleset FlatBuffer.
static bool Verify(const uint8_t* buffer, size_t size, int expected_checksum);
// Creates an instance that matches URLs against the flat::IndexedRuleset
// provided as the root object of serialized data in the |buffer| of the given
// |size|.
IndexedRulesetMatcher(const uint8_t* buffer, size_t size);
// Returns whether the subset of subresource filtering rules specified by the
// |activation_type| should be disabled for the |document| loaded from
// |parent_document_origin|. Always returns false if |activation_type| ==
// ACTIVATION_TYPE_UNSPECIFIED or the |document_url| is not valid. Unlike
// page-level activation, such rules can be used to have fine-grained control
// over the activation of filtering within (sub-)documents.
bool ShouldDisableFilteringForDocument(
const GURL& document_url,
const url::Origin& parent_document_origin,
url_pattern_index::proto::ActivationType activation_type) const;
// Returns whether the network request to |url| of |element_type| initiated by
// |document_origin| is not allowed to proceed. Always returns false if the
// |url| is not valid or |element_type| == ELEMENT_TYPE_UNSPECIFIED.
bool ShouldDisallowResourceLoad(
const GURL& url,
const FirstPartyOrigin& first_party,
url_pattern_index::proto::ElementType element_type,
bool disable_generic_rules) const;
// Like ShouldDisallowResourceLoad, but returns the matching rule that
// determines whether the request should be allowed or not. Whitelist rules
// override blacklist rules. If no rule matches, returns nullptr.
const url_pattern_index::flat::UrlRule* MatchedUrlRule(
const GURL& url,
const FirstPartyOrigin& first_party,
url_pattern_index::proto::ElementType element_type,
bool disable_generic_rules) const;
const flat::IndexedRuleset* root_;
url_pattern_index::UrlPatternIndexMatcher blacklist_;
url_pattern_index::UrlPatternIndexMatcher whitelist_;
url_pattern_index::UrlPatternIndexMatcher deactivation_;
} // namespace subresource_filter