chromium/services/preferences/tracked/pref_hash_calculator.cc

// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "services/preferences/tracked/pref_hash_calculator.h"

#include <stdint.h>

#include <memory>
#include <vector>

#include "base/functional/bind.h"
#include "base/json/json_string_value_serializer.h"
#include "base/notreached.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/values.h"
#include "crypto/hmac.h"

namespace {

// Calculates an HMAC of |message| using |key|, encoded as a hexadecimal string.
std::string GetDigestString(const std::string& key,
                            const std::string& message) { … }

void RemoveEmptyValueDictEntries(base::Value::Dict& dict);
void RemoveEmptyValueListEntries(base::Value::List& list);

// Removes empty Dict and List Values from |dict|, potentially nested.
// This function may leave |dict| empty, and |dict| may be empty when passed in.
void RemoveEmptyValueDictEntries(base::Value::Dict& dict) { … }

// Removes empty Dict and List Values from |list|, potentially nested.
// This function may leave |list| empty, and |list| may be empty when passed in.
void RemoveEmptyValueListEntries(base::Value::List& list) { … }

// Verifies that |digest_string| is a valid HMAC of |message| using |key|.
// |digest_string| must be encoded as a hexadecimal string.
bool VerifyDigestString(const std::string& key,
                        const std::string& message,
                        const std::string& digest_string) { … }

// Renders |value| as a string. |value| may be NULL, in which case the result
// is an empty string. This method can be expensive and its result should be
// re-used rather than recomputed where possible.

std::string ValueAsString(const base::Value::Dict* value) { … }

std::string ValueAsString(const base::Value* value) { … }

// Concatenates |device_id|, |path|, and |value_as_string| to give the hash
// input.
std::string GetMessage(const std::string& device_id,
                       const std::string& path,
                       const std::string& value_as_string) { … }

}  // namespace

PrefHashCalculator::PrefHashCalculator(const std::string& seed,
                                       const std::string& device_id,
                                       const std::string& legacy_device_id)
    : … { … }

PrefHashCalculator::~PrefHashCalculator() { … }

std::string PrefHashCalculator::Calculate(const std::string& path,
                                          const base::Value* value) const { … }

std::string PrefHashCalculator::Calculate(const std::string& path,
                                          const base::Value::Dict* dict) const { … }

PrefHashCalculator::ValidationResult PrefHashCalculator::Validate(
    const std::string& path,
    const base::Value* value,
    const std::string& digest_string) const { … }

PrefHashCalculator::ValidationResult PrefHashCalculator::Validate(
    const std::string& path,
    const base::Value::Dict* dict,
    const std::string& digest_string) const { … }

PrefHashCalculator::ValidationResult PrefHashCalculator::Validate(
    const std::string& path,
    const std::string& value_as_string,
    const std::string& digest_string) const { … }