1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138
  139
  140

content / browser / blob_storage / file_backed_blob_factory_base.cc [blame]

// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/blob_storage/file_backed_blob_factory_base.h"

#include "base/functional/callback_helpers.h"
#include "base/process/process_handle.h"
#include "base/task/bind_post_task.h"
#include "base/task/sequenced_task_runner.h"
#include "content/browser/blob_storage/chrome_blob_storage_context.h"
#include "content/browser/child_process_security_policy_impl.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/render_process_host.h"
#include "storage/browser/blob/blob_data_builder.h"
#include "storage/browser/blob/blob_impl.h"
#include "storage/browser/blob/blob_registry_impl.h"
#include "third_party/blink/public/mojom/blob/data_element.mojom.h"
#include "url/gurl.h"

namespace content {

namespace {

file_access::ScopedFileAccessDelegate::RequestFilesAccessIOCallback
GetAccessCallback(const GURL& url_for_file_access_checks) {
  if (!file_access::ScopedFileAccessDelegate::HasInstance() ||
      !url_for_file_access_checks.is_valid()) {
    return base::NullCallback();
  }

  file_access::ScopedFileAccessDelegate* file_access =
      file_access::ScopedFileAccessDelegate::Get();
  CHECK(file_access);

  return file_access->CreateFileAccessCallback(url_for_file_access_checks);
}

void ContinueRegisterBlob(
    mojo::PendingReceiver<blink::mojom::Blob> blob,
    std::string uuid,
    std::string content_type,
    blink::mojom::DataElementFilePtr file,
    file_access::ScopedFileAccessDelegate::RequestFilesAccessIOCallback
        file_access,
    bool security_check_success,
    mojo::ReportBadMessageCallback bad_message_callback,
    scoped_refptr<ChromeBlobStorageContext> blob_storage_context,
    blink::mojom::FileBackedBlobFactory::RegisterBlobSyncCallback
        finish_callback) {
  DCHECK_CURRENTLY_ON(BrowserThread::IO);
  base::ScopedClosureRunner scoped_finish_callback(std::move(finish_callback));

  if (blob_storage_context->context()->registry().HasEntry(uuid) ||
      uuid.empty()) {
    std::move(bad_message_callback)
        .Run("Invalid UUID passed to FileBackedBlobFactoryImpl::RegisterBlob");
    return;
  }

  if (!security_check_success) {
    std::unique_ptr<storage::BlobDataHandle> handle =
        blob_storage_context->context()->AddBrokenBlob(
            uuid, content_type, /*content_disposition=*/"",
            storage::BlobStatus::ERR_REFERENCED_FILE_UNAVAILABLE);
    storage::BlobImpl::Create(std::move(handle), std::move(blob));
    return;
  }

  auto builder = std::make_unique<storage::BlobDataBuilder>(uuid);
  if (file->length > 0) {
    builder->AppendFile(file->path, file->offset, file->length,
                        file->expected_modification_time.value_or(base::Time()),
                        file_access);
  }
  builder->set_content_type(content_type);

  std::unique_ptr<storage::BlobDataHandle> handle =
      blob_storage_context->context()->AddFinishedBlob(std::move(builder));

  CHECK(!handle->IsBroken());

  storage::BlobImpl::Create(std::move(handle), std::move(blob));
}

}  // namespace

FileBackedBlobFactoryBase::FileBackedBlobFactoryBase(int process_id)
    : process_id_(process_id) {}

FileBackedBlobFactoryBase::~FileBackedBlobFactoryBase() = default;

void FileBackedBlobFactoryBase::RegisterBlob(
    mojo::PendingReceiver<blink::mojom::Blob> blob,
    const std::string& uuid,
    const std::string& content_type,
    blink::mojom::DataElementFilePtr file) {
  // We can safely perform the registration asynchronously since blob remote
  // messages are managed by the mojo infrastructure until the blob pending
  // receiver is resolved, and this happens when the async registration is
  // completed. Without the mojo continuation callback the `RegisterBlobSync`
  // call is async.

  RegisterBlobSync(std::move(blob), uuid, content_type, std::move(file),
                   base::NullCallback());
}

void FileBackedBlobFactoryBase::RegisterBlobSync(
    mojo::PendingReceiver<blink::mojom::Blob> blob,
    const std::string& uuid,
    const std::string& content_type,
    blink::mojom::DataElementFilePtr file,
    RegisterBlobSyncCallback finish_callback) {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);

  bool security_check_success =
      ChildProcessSecurityPolicyImpl::GetInstance()->CanReadFile(process_id_,
                                                                 file->path);

  GURL url_for_file_access_checks = GetCurrentUrl();

  if (finish_callback) {
    finish_callback =
        base::BindPostTask(base::SequencedTaskRunner::GetCurrentDefault(),
                           std::move(finish_callback));
  }

  content::GetIOThreadTaskRunner({})->PostTask(
      FROM_HERE,
      base::BindOnce(&ContinueRegisterBlob, std::move(blob), uuid, content_type,
                     std::move(file),
                     GetAccessCallback(url_for_file_access_checks),
                     security_check_success,
                     base::BindPostTask(GetUIThreadTaskRunner({}),
                                        GetBadMessageCallback()),
                     blob_storage_context_, std::move(finish_callback)));
}

}  // namespace content