extensions/common/manifest_handler_helpers.cc

// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "extensions/common/manifest_handler_helpers.h"

#include <stddef.h>

#include <optional>
#include <string>
#include <string_view>

#include "base/check.h"
#include "base/files/file_path.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/values.h"
#include "extensions/common/constants.h"
#include "extensions/common/error_utils.h"
#include "extensions/common/extension.h"
#include "extensions/common/extension_resource.h"
#include "extensions/common/icons/extension_icon_set.h"
#include "extensions/common/manifest_constants.h"
#include "net/base/mime_util.h"
#include "third_party/blink/public/common/mime_util/mime_util.h"

namespace extensions {

namespace errors = manifest_errors;

namespace manifest_handler_helpers {

std::vector<std::string_view> TokenizeDictionaryPath(std::string_view path) {
  return base::SplitStringPiece(path, ".", base::TRIM_WHITESPACE,
                                base::SPLIT_WANT_ALL);
}

std::optional<int> LoadValidSizeFromString(const std::string& string_size) {
  int size = 0;
  bool is_valid = base::StringToInt(string_size, &size) && size > 0 &&
                  size <= extension_misc::EXTENSION_ICON_GIGANTOR * 4;
  return is_valid ? std::make_optional(size) : std::nullopt;
}

bool LoadIconsFromDictionary(const Extension& extension,
                             const base::Value::Dict& icons_value,
                             ExtensionIconSet* icons,
                             std::u16string* error,
                             std::vector<std::string>* warnings) {
  DCHECK(icons);
  DCHECK(error);
  for (auto entry : icons_value) {
    std::optional<int> size = LoadValidSizeFromString(entry.first);
    if (!size.has_value()) {
      *error = ErrorUtils::FormatErrorMessageUTF16(errors::kInvalidIconKey,
                                                   entry.first);
      return false;
    }
    if (!entry.second.is_string()) {
      *error = ErrorUtils::FormatErrorMessageUTF16(errors::kInvalidIconPath,
                                                   entry.first);
      return false;
    }
    ExtensionResource icon_path =
        extension.GetResource(entry.second.GetString());
    if (icon_path.empty()) {
      *error = ErrorUtils::FormatErrorMessageUTF16(errors::kInvalidIconPath,
                                                   entry.first);
      return false;
    }
    if (!IsIconMimeTypeValid(icon_path.relative_path())) {
      // Issue a warning and ignore this file. This is a warning and not a
      // hard-error to preserve both backwards compatibility and potential
      // future-compatibility if mime types change.
      warnings->emplace_back(ErrorUtils::FormatErrorMessage(
          errors::kInvalidIconMimeType, entry.first));
      continue;
    }

    icons->Add(size.value(), icon_path.relative_path().AsUTF8Unsafe());
  }
  return true;
}

bool IsSupportedExtensionImageMimeType(const base::FilePath& relative_path) {
  std::string mime_type;
  if (!net::GetWellKnownMimeTypeFromFile(relative_path, &mime_type)) {
    return false;
  }

  // SVG is text-based XML, even though it has an "image/" type. Allow it
  // explicitly.
  constexpr char kSvgMimeType[] = "image/svg+xml";

  return blink::IsSupportedImageMimeType(mime_type) ||
         mime_type == kSvgMimeType;
}

bool IsIconMimeTypeValid(const base::FilePath& relative_path) {
  return IsSupportedExtensionImageMimeType(relative_path);
}

}  // namespace manifest_handler_helpers

}  // namespace extensions