skia_image_filter_proto_converter.cc

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

// Converts an Input protobuf Message to a string that can be successfully read
// by SkImageFilter::Deserialize and used as an image filter. The string
// is essentially a valid flattened skia image filter. Note: We will sometimes
// not use the exact values given to us by LPM in cases where those particular
// values cause issues with OOMs and timeouts. Other times, we may write a value
// that isn't exactly the same as the one given to us by LPM, since we may want
// to write invalid values that the proto definition forbids (eg a number that
// is not in enum).  Also note that the skia unflattening code is necessary to
// apply the output of the converter to a canvas, but it isn't the main target
// of the fuzzer. This means that we will generally try to produce output that
// can be applied to a canvas, even if we will consequently be unable to produce
// outputs that allow us to reach paths in the unflattening code (in particular,
// code that handles invalid input). We make this tradeoff because being applied
// to a canvas makes an image filter more likely to cause bugs than if it were
// just deserialized.  Thus, increasing the chance that a filter is applied is
// more important than hitting all paths in unflattening, particularly if those
// paths return nullptr because they've detected an invalid filter. The mutated
// enum values are a case where we knowingly generate output that may not be
// unflattened successfully, which is why we mutate enums relatively
// infrequently.
// Note that since this is a work in progress and skia serialization is a
// moving target, not everything is finished. Many of these parts of the code
// are #defined out if DEVELOPMENT is not defined.

#include "testing/libfuzzer/proto/skia_image_filter_proto_converter.h"

#include <stdlib.h>

#include <algorithm>
#include <cmath>
#include <limits>
#include <random>
#include <set>
#include <string>
#include <tuple>
#include <unordered_map>
#include <vector>

#include "base/check_op.h"
#include "base/containers/contains.h"
#include "base/containers/span.h"
#include "base/notreached.h"
#include "base/numerics/byte_conversions.h"
#include "base/numerics/safe_conversions.h"
#include "third_party/protobuf/src/google/protobuf/descriptor.h"
#include "third_party/protobuf/src/google/protobuf/message.h"
#include "third_party/protobuf/src/google/protobuf/repeated_field.h"
#include "third_party/skia/include/core/SkPoint.h"
#include "third_party/skia/include/core/SkRect.h"

Descriptor;
EnumDescriptor;
EnumValueDescriptor;
FieldDescriptor;
Message;
Reflection;

skia_image_filter_proto_converter  // namespace skia_image_filter_proto_converter
chromium/testing/libfuzzer/proto/skia_image_filter_proto_converter.cc
