orb_mimetypes.cc | Explore in Territory

// 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.

#include "services/network/orb/orb_mimetypes.h"

#include <stddef.h>

#include <set>
#include <string>
#include <unordered_set>
#include <vector>

#include "base/check_op.h"
#include "base/command_line.h"
#include "base/containers/contains.h"
#include "base/containers/fixed_flat_set.h"
#include "base/feature_list.h"
#include "base/lazy_instance.h"
#include "base/metrics/histogram_macros.h"
#include "base/notreached.h"
#include "base/ranges/algorithm.h"
#include "base/strings/string_util.h"
#include "net/base/mime_sniffer.h"
#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
#include "net/http/http_response_headers.h"
#include "services/network/public/cpp/cross_origin_embedder_policy.h"
#include "services/network/public/cpp/features.h"
#include "services/network/public/cpp/initiator_lock_compatibility.h"
#include "services/network/public/mojom/network_context.mojom.h"
#include "services/network/public/mojom/network_service.mojom.h"
#include "services/network/public/mojom/url_response_head.mojom.h"

namespace network::orb {

namespace {

// MIME types
const char kTextHtml[] = …;
const char kTextXml[] = …;
const char kAppXml[] = …;
const char kAppJson[] = …;
const char kImageSvg[] = …;
const char kDashVideo[] = …;  // https://crbug.com/947498
const char kTextJson[] = …;
const char kTextPlain[] = …;

// Javascript MIME type suffixes for use in CORB protection logging. See also
// https://mimesniff.spec.whatwg.org/#javascript-mime-type.
const char* kJavaScriptSuffixes[] = …;

// TODO(lukasza): Remove kJsonProtobuf once this MIME type is not used in
// practice.  See also https://crbug.com/826756#c3
const char kJsonProtobuf[] = …;

// MIME type suffixes
const char kJsonSuffix[] = …;
const char kXmlSuffix[] = …;

// The function below returns a set of MIME types below may be blocked by CORB
// without any confirmation sniffing (in contrast to HTML/JSON/XML which require
// confirmation sniffing because images, scripts, etc. are frequently
// mislabelled by http servers as HTML/JSON/XML).
//
// CORB cannot block images, scripts, stylesheets and other resources that the
// web standards allows to be fetched in `no-cors` mode.  CORB cannot block
// these resources even if they are not explicitly labeled with their type - in
// practice http servers may serve images as application/octet-stream or even as
// text/html.  OTOH, CORB *can* block all Content-Types that are very unlikely
// to represent images, scripts, stylesheets, etc. - such Content-Types are
// returned by GetNeverSniffedMimeTypes.
//
// Some of the Content-Types returned below might seem like a layering violation
// (e.g. why would //services/network care about application/zip or
// application/pdf or application/msword), but note that the decision to list a
// Content-Type below is not driven by whether the type is handled above or
// below //services/network layer.  Instead the decision to list a Content-Type
// below is driven by whether the Content-Type is unlikely to be attached to an
// image, script, stylesheet or other subresource type that web standards
// require to be fetched in `no-cors` mode.  In particular, CORB would still
// want to prevent cross-site disclosure of "application/msword" even if Chrome
// did not support this type (AFAIK today this support is only present on
// ChromeOS) in one of Chrome's many layers.  Similarly, CORB wants to prevent
// disclosure of "application/zip" even though Chrome doesn't have built-in
// support for this resource type.  And CORB also wants to protect
// "application/pdf" even though Chrome happens to support this resource type.
const auto& GetNeverSniffedMimeTypes() { … }

}  // namespace

bool IsJavascriptMimeType(std::string_view mime_type) { … }

MimeType GetCanonicalMimeType(std::string_view mime_type) { … }

}  // namespace network::orb
chromium/services/network/orb/orb_mimetypes.cc
