/src/FreeRDP/winpr/libwinpr/clipboard/synthetic_file.c

Source
/**
 * WinPR: Windows Portable Runtime
 * Clipboard Functions: POSIX file handling
 *
 * Copyright 2017 Alexei Lozovsky <a.lozovsky@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <winpr/config.h>
#include <winpr/platform.h>

WINPR_PRAGMA_DIAG_PUSH
WINPR_PRAGMA_DIAG_IGNORED_RESERVED_ID_MACRO
WINPR_PRAGMA_DIAG_IGNORED_UNUSED_MACRO

#define _FILE_OFFSET_BITS 64 // NOLINT(bugprone-reserved-identifier,cert-dcl37-c,cert-dcl51-cpp)

WINPR_PRAGMA_DIAG_POP

#include <errno.h>

#include <winpr/wtypes.h>

#include <winpr/crt.h>
#include <winpr/clipboard.h>
#include <winpr/collections.h>
#include <winpr/file.h>
#include <winpr/shell.h>
#include <winpr/string.h>
#include <winpr/wlog.h>
#include <winpr/path.h>
#include <winpr/print.h>

#include "clipboard.h"
#include "synthetic_file.h"

#include "../log.h"
#define TAG WINPR_TAG("clipboard.synthetic.file")

static const char* mime_uri_list = "text/uri-list";
static const char* mime_FileGroupDescriptorW = "FileGroupDescriptorW";
static const char* mime_gnome_copied_files = "x-special/gnome-copied-files";
static const char* mime_mate_copied_files = "x-special/mate-copied-files";

struct synthetic_file
{
  WCHAR* local_name;
  WCHAR* remote_name;

  HANDLE fd;
  INT64 offset;

  DWORD dwFileAttributes;
  FILETIME ftCreationTime;
  FILETIME ftLastAccessTime;
  FILETIME ftLastWriteTime;
  DWORD nFileSizeHigh;
  DWORD nFileSizeLow;
};

void free_synthetic_file(struct synthetic_file* file);

static struct synthetic_file* make_synthetic_file(const WCHAR* local_name, const WCHAR* remote_name)
{
  struct synthetic_file* file = nullptr;
  WIN32_FIND_DATAW fd = WINPR_C_ARRAY_INIT;
  HANDLE hFind = nullptr;

  WINPR_ASSERT(local_name);
  WINPR_ASSERT(remote_name);

  hFind = FindFirstFileW(local_name, &fd);
  if (INVALID_HANDLE_VALUE == hFind)
  {
    WLog_ERR(TAG, "FindFirstFile failed (%" PRIu32 ")", GetLastError());
    return nullptr;
  }
  FindClose(hFind);

  file = calloc(1, sizeof(*file));
  if (!file)
    return nullptr;

  file->fd = INVALID_HANDLE_VALUE;
  file->offset = 0;
  file->local_name = _wcsdup(local_name);
  if (!file->local_name)
    goto fail;

  file->remote_name = _wcsdup(remote_name);
  if (!file->remote_name)
    goto fail;

  {
    const size_t len = _wcslen(file->remote_name);
    if (S_OK != PathCchConvertStyleW(file->remote_name, len, PATH_STYLE_WINDOWS))
      goto fail;
  }

  file->dwFileAttributes = fd.dwFileAttributes;
  file->ftCreationTime = fd.ftCreationTime;
  file->ftLastWriteTime = fd.ftLastWriteTime;
  file->ftLastAccessTime = fd.ftLastAccessTime;
  file->nFileSizeHigh = fd.nFileSizeHigh;
  file->nFileSizeLow = fd.nFileSizeLow;

  return file;
fail:
  free_synthetic_file(file);
  return nullptr;
}

static UINT synthetic_file_read_close(struct synthetic_file* file, BOOL force);

void free_synthetic_file(struct synthetic_file* file)
{
  if (!file)
    return;

  synthetic_file_read_close(file, TRUE);

  free(file->local_name);
  free(file->remote_name);
  free(file);
}

/*
 * Note that the function converts a single file name component,
 * it does not take care of component separators.
 */
static WCHAR* convert_local_name_component_to_remote(wClipboard* clipboard, const WCHAR* local_name)
{
  wClipboardDelegate* delegate = ClipboardGetDelegate(clipboard);
  WCHAR* remote_name = nullptr;

  WINPR_ASSERT(delegate);

  remote_name = _wcsdup(local_name);

  /*
   * Some file names are not valid on Windows. Check for these now
   * so that we won't get ourselves into a trouble later as such names
   * are known to crash some Windows shells when pasted via clipboard.
   *
   * The IsFileNameComponentValid callback can be overridden by the API
   * user, if it is known, that the connected peer is not on the
   * Windows platform.
   */
  if (!delegate->IsFileNameComponentValid(remote_name))
  {
    char name[MAX_PATH] = WINPR_C_ARRAY_INIT;
    ConvertWCharToUtf8(local_name, name, sizeof(name) - 1);
    WLog_ERR(TAG, "invalid file name component: %s", name);
    goto error;
  }

  return remote_name;
error:
  free(remote_name);
  return nullptr;
}

static WCHAR* concat_file_name(const WCHAR* dir, const WCHAR* file)
{
  size_t len_dir = 0;
  size_t len_file = 0;
  const WCHAR slash = '/';
  WCHAR* buffer = nullptr;

  WINPR_ASSERT(dir);
  WINPR_ASSERT(file);

  len_dir = _wcslen(dir);
  len_file = _wcslen(file);
  buffer = calloc(len_dir + 1 + len_file + 2, sizeof(WCHAR));

  if (!buffer)
    return nullptr;

  memcpy(buffer, dir, len_dir * sizeof(WCHAR));
  buffer[len_dir] = slash;
  memcpy(buffer + len_dir + 1, file, len_file * sizeof(WCHAR));
  return buffer;
}

static BOOL add_file_to_list(wClipboard* clipboard, size_t recursionDepth, const WCHAR* local_name,
                             const WCHAR* remote_name, wArrayList* files);

static BOOL add_directory_entry_to_list(wClipboard* clipboard, size_t recursionDepth,
                                        const WCHAR* local_dir_name, const WCHAR* remote_dir_name,
                                        const LPWIN32_FIND_DATAW pFileData, wArrayList* files)
{
  BOOL result = FALSE;
  WCHAR* local_name = nullptr;
  WCHAR* remote_name = nullptr;
  WCHAR* remote_base_name = nullptr;

  WCHAR dotbuffer[6] = WINPR_C_ARRAY_INIT;
  WCHAR dotdotbuffer[6] = WINPR_C_ARRAY_INIT;
  const WCHAR* dot = InitializeConstWCharFromUtf8(".", dotbuffer, ARRAYSIZE(dotbuffer));
  const WCHAR* dotdot = InitializeConstWCharFromUtf8("..", dotdotbuffer, ARRAYSIZE(dotdotbuffer));

  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(local_dir_name);
  WINPR_ASSERT(remote_dir_name);
  WINPR_ASSERT(pFileData);
  WINPR_ASSERT(files);

  /* Skip special directory entries. */

  if ((_wcscmp(pFileData->cFileName, dot) == 0) || (_wcscmp(pFileData->cFileName, dotdot) == 0))
    return TRUE;

  remote_base_name = convert_local_name_component_to_remote(clipboard, pFileData->cFileName);

  if (!remote_base_name)
    return FALSE;

  local_name = concat_file_name(local_dir_name, pFileData->cFileName);
  remote_name = concat_file_name(remote_dir_name, remote_base_name);

  if (local_name && remote_name)
    result = add_file_to_list(clipboard, recursionDepth, local_name, remote_name, files);

  free(remote_base_name);
  free(remote_name);
  free(local_name);
  return result;
}

static BOOL do_add_directory_contents_to_list(wClipboard* clipboard, size_t recursionDepth,
                                              const WCHAR* local_name, const WCHAR* remote_name,
                                              WCHAR* namebuf, wArrayList* files)
{
  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(local_name);
  WINPR_ASSERT(remote_name);
  WINPR_ASSERT(files);
  WINPR_ASSERT(namebuf);

  WIN32_FIND_DATAW FindData = WINPR_C_ARRAY_INIT;
  HANDLE hFind = FindFirstFileW(namebuf, &FindData);
  if (INVALID_HANDLE_VALUE == hFind)
  {
    WLog_ERR(TAG, "FindFirstFile failed (%" PRIu32 ")", GetLastError());
    return FALSE;
  }
  while (TRUE)
  {
    if (!add_directory_entry_to_list(clipboard, recursionDepth, local_name, remote_name,
                                     &FindData, files))
    {
      FindClose(hFind);
      return FALSE;
    }

    BOOL bRet = FindNextFileW(hFind, &FindData);
    if (!bRet)
    {
      FindClose(hFind);
      if (ERROR_NO_MORE_FILES == GetLastError())
        return TRUE;
      WLog_WARN(TAG, "FindNextFile failed (%" PRIu32 ")", GetLastError());
      return FALSE;
    }
  }

  return TRUE;
}

static BOOL add_directory_contents_to_list(wClipboard* clipboard, size_t recursionDepth,
                                           const WCHAR* local_name, const WCHAR* remote_name,
                                           wArrayList* files)
{
  BOOL result = FALSE;
  union
  {
    const char* c;
    const WCHAR* w;
  } wildcard;
  const char buffer[6] = { '/', '\0', '*', '\0', '\0', '\0' };
  wildcard.c = buffer;
  const size_t wildcardLen = ARRAYSIZE(buffer) / sizeof(WCHAR);

  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(local_name);
  WINPR_ASSERT(remote_name);
  WINPR_ASSERT(files);

  const size_t max = CLIPBOARD_FILE_MAX_RECURSION;
  if (recursionDepth > max)
  {
    WLog_ERR(TAG,
             "This build only supports recursionDepth=%" PRIuz
             " <= CLIPBOARD_FILE_MAX_RECURSION=%" PRIuz " recursion depth for folders copied.",
             recursionDepth, max);
    return FALSE;
  }

  size_t len = _wcslen(local_name);
  WCHAR* namebuf = calloc(len + wildcardLen, sizeof(WCHAR));
  if (!namebuf)
    return FALSE;

  _wcsncat(namebuf, local_name, len);
  _wcsncat(namebuf, wildcard.w, wildcardLen);

  result = do_add_directory_contents_to_list(clipboard, recursionDepth, local_name, remote_name,
                                             namebuf, files);

  free(namebuf);
  return result;
}

BOOL add_file_to_list(wClipboard* clipboard, size_t recursionDepth, const WCHAR* local_name,
                      const WCHAR* remote_name, wArrayList* files)
{
  struct synthetic_file* file = nullptr;

  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(local_name);
  WINPR_ASSERT(remote_name);
  WINPR_ASSERT(files);

  file = make_synthetic_file(local_name, remote_name);

  if (!file)
    return FALSE;

  if (!ArrayList_Append(files, file))
  {
    free_synthetic_file(file);
    return FALSE;
  }

  if (file->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
  {
    /*
     * This is effectively a recursive call, but we do not track
     * recursion depth, thus filesystem loops can cause a crash.
     */
    if (!add_directory_contents_to_list(clipboard, recursionDepth + 1, local_name, remote_name,
                                        files))
      return FALSE;
  }

  return TRUE;
}

static const WCHAR* get_basename(const WCHAR* name)
{
  const WCHAR* c = name;
  const WCHAR* last_name = name;
  const WCHAR slash = '/';

  WINPR_ASSERT(name);

  while (*c++)
  {
    if (*c == slash)
      last_name = c + 1;
  }

  return last_name;
}

static BOOL process_file_name(wClipboard* clipboard, const WCHAR* local_name, wArrayList* files)
{
  BOOL result = FALSE;
  const WCHAR* base_name = nullptr;
  WCHAR* remote_name = nullptr;

  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(local_name);
  WINPR_ASSERT(files);

  /*
   * Start with the base name of the file. text/uri-list contains the
   * exact files selected by the user, and we want the remote files
   * to have names relative to that selection.
   */
  base_name = get_basename(local_name);
  remote_name = convert_local_name_component_to_remote(clipboard, base_name);

  if (!remote_name)
    return FALSE;

  result = add_file_to_list(clipboard, 0, local_name, remote_name, files);
  free(remote_name);
  return result;
}

static BOOL process_uri(wClipboard* clipboard, const char* uri, size_t uri_len)
{
  // URI is specified by RFC 8089: https://datatracker.ietf.org/doc/html/rfc8089
  BOOL result = FALSE;
  char* name = nullptr;

  WINPR_ASSERT(clipboard);

  name = parse_uri_to_local_file(uri, uri_len);
  if (name)
  {
    WCHAR* wname = nullptr;
    /*
     * Note that local file names are not actually guaranteed to be
     * encoded in UTF-8. Filesystems and users can use whatever they
     * want. The OS does not care, aside from special treatment of
     * '\0' and '/' bytes. But we need to make some decision here.
     * Assuming UTF-8 is currently the most sane thing.
     */
    wname = ConvertUtf8ToWCharAlloc(name, nullptr);
    if (wname)
      result = process_file_name(clipboard, wname, clipboard->localFiles);

    free(name);
    free(wname);
  }

  return result;
}

static BOOL process_uri_list(wClipboard* clipboard, const char* data, size_t length)
{
  const char* cur = data;
  const char* lim = data + length;

  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(data);

  WLog_VRB(TAG, "processing URI list:\n%.*s", WINPR_ASSERTING_INT_CAST(int, length), data);
  ArrayList_Clear(clipboard->localFiles);

  /*
   * The "text/uri-list" Internet Media Type is specified by RFC 2483.
   *
   * While the RFCs 2046 and 2483 require the lines of text/... formats
   * to be terminated by CRLF sequence, be prepared for those who don't
   * read the spec, use plain LFs, and don't leave the trailing CRLF.
   */

  while (cur < lim)
  {
    BOOL comment = (*cur == '#');
    const char* start = cur;
    const char* stop = cur;

    for (; stop < lim; stop++)
    {
      if (*stop == '\r')
      {
        if ((stop + 1 < lim) && (*(stop + 1) == '\n'))
          cur = stop + 2;
        else
          cur = stop + 1;

        break;
      }

      if (*stop == '\n')
      {
        cur = stop + 1;
        break;
      }
    }

    if (stop == lim)
    {
      if (strnlen(start, WINPR_ASSERTING_INT_CAST(size_t, stop - start)) < 1)
        return TRUE;
      cur = lim;
    }

    if (comment)
      continue;

    if (!process_uri(clipboard, start, WINPR_ASSERTING_INT_CAST(size_t, stop - start)))
      return FALSE;
  }

  return TRUE;
}

static BOOL convert_local_file_to_filedescriptor(const struct synthetic_file* file,
                                                 FILEDESCRIPTORW* descriptor)
{
  size_t remote_len = 0;

  WINPR_ASSERT(file);
  WINPR_ASSERT(descriptor);

  descriptor->dwFlags = FD_ATTRIBUTES | FD_FILESIZE | FD_WRITESTIME | FD_PROGRESSUI;

  if (file->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
  {
    descriptor->dwFileAttributes = FILE_ATTRIBUTE_DIRECTORY;
    descriptor->nFileSizeLow = 0;
    descriptor->nFileSizeHigh = 0;
  }
  else
  {
    descriptor->dwFileAttributes = FILE_ATTRIBUTE_NORMAL;
    descriptor->nFileSizeLow = file->nFileSizeLow;
    descriptor->nFileSizeHigh = file->nFileSizeHigh;
  }

  descriptor->ftLastWriteTime = file->ftLastWriteTime;

  remote_len = _wcsnlen(file->remote_name, ARRAYSIZE(descriptor->cFileName));

  if (remote_len >= ARRAYSIZE(descriptor->cFileName))
  {
    WLog_ERR(TAG, "file name too long (%" PRIuz " characters)", remote_len);
    return FALSE;
  }

  memcpy(descriptor->cFileName, file->remote_name, remote_len * sizeof(WCHAR));
  return TRUE;
}

static FILEDESCRIPTORW* convert_local_file_list_to_filedescriptors(wArrayList* files)
{
  size_t count = 0;
  FILEDESCRIPTORW* descriptors = nullptr;

  count = ArrayList_Count(files);

  descriptors = calloc(count, sizeof(FILEDESCRIPTORW));

  if (!descriptors)
    goto error;

  for (size_t i = 0; i < count; i++)
  {
    const struct synthetic_file* file = ArrayList_GetItem(files, i);

    if (!convert_local_file_to_filedescriptor(file, &descriptors[i]))
      goto error;
  }

  return descriptors;
error:
  free(descriptors);
  return nullptr;
}

static void* convert_any_uri_list_to_filedescriptors(wClipboard* clipboard,
                                                     WINPR_ATTR_UNUSED UINT32 formatId,
                                                     UINT32* pSize)
{
  FILEDESCRIPTORW* descriptors = nullptr;

  WINPR_ASSERT(clipboard);
  WINPR_ASSERT(pSize);

  descriptors = convert_local_file_list_to_filedescriptors(clipboard->localFiles);
  *pSize = 0;
  if (!descriptors)
    return nullptr;

  *pSize = (UINT32)ArrayList_Count(clipboard->localFiles) * sizeof(FILEDESCRIPTORW);
  clipboard->fileListSequenceNumber = clipboard->sequenceNumber;
  return descriptors;
}

static void* convert_uri_list_to_filedescriptors(wClipboard* clipboard, UINT32 formatId,
                                                 const void* data, UINT32* pSize)
{
  if (formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_uri_list))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (!process_uri_list(clipboard, (const char*)data, *pSize))
    return nullptr;
  return convert_any_uri_list_to_filedescriptors(clipboard, clipboard->formatId, pSize);
}

static BOOL process_files(wClipboard* clipboard, const char* data, UINT32 pSize, const char* prefix)
{
  WINPR_ASSERT(prefix);

  const size_t prefix_len = strlen(prefix);

  WINPR_ASSERT(clipboard);

  ArrayList_Clear(clipboard->localFiles);

  if (!data || (pSize < prefix_len))
    return FALSE;
  if (strncmp(data, prefix, prefix_len) != 0)
    return FALSE;
  data += prefix_len;
  if (pSize < prefix_len)
    return FALSE;
  pSize -= WINPR_ASSERTING_INT_CAST(uint32_t, prefix_len);

  BOOL rc = FALSE;
  char* copy = strndup(data, pSize);
  if (!copy)
    goto fail;

  {
    char* endptr = nullptr;
    char* tok = strtok_s(copy, "\n", &endptr);
    while (tok)
    {
      const size_t tok_len = strnlen(tok, pSize);
      if (!process_uri(clipboard, tok, tok_len))
        goto fail;
      if (pSize < tok_len)
        goto fail;
      pSize -= WINPR_ASSERTING_INT_CAST(uint32_t, tok_len);
      tok = strtok_s(nullptr, "\n", &endptr);
    }
  }

  rc = TRUE;

fail:
  free(copy);
  return rc;
}

static BOOL process_gnome_copied_files(wClipboard* clipboard, const char* data, UINT32 pSize)
{
  return process_files(clipboard, data, pSize, "copy\n");
}

static BOOL process_mate_copied_files(wClipboard* clipboard, const char* data, UINT32 pSize)
{
  return process_files(clipboard, data, pSize, "copy\n");
}

static void* convert_gnome_copied_files_to_filedescriptors(wClipboard* clipboard, UINT32 formatId,
                                                           const void* data, UINT32* pSize)
{
  if (formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_gnome_copied_files))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (!process_gnome_copied_files(clipboard, (const char*)data, *pSize))
    return nullptr;
  return convert_any_uri_list_to_filedescriptors(clipboard, clipboard->formatId, pSize);
}

static void* convert_mate_copied_files_to_filedescriptors(wClipboard* clipboard, UINT32 formatId,
                                                          const void* data, UINT32* pSize)
{
  if (formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_mate_copied_files))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }

  if (!process_mate_copied_files(clipboard, (const char*)data, *pSize))
    return nullptr;

  return convert_any_uri_list_to_filedescriptors(clipboard, formatId, pSize);
}

WINPR_ATTR_NODISCARD
static size_t count_special_chars(const WCHAR* str, size_t charLen)
{
  size_t count = 0;
  const WCHAR* start = str;
  const WCHAR* end = &str[charLen];

  WINPR_ASSERT(str);
  while ((start < end) && (*start))
  {
    const WCHAR sharp = '#';
    const WCHAR questionmark = '?';
    const WCHAR star = '*';
    const WCHAR exclamationmark = '!';
    const WCHAR percent = '%';

    if ((*start == sharp) || (*start == questionmark) || (*start == star) ||
        (*start == exclamationmark) || (*start == percent))
    {
      count++;
    }
    start++;
  }
  return count;
}

static const char* stop_at_special_chars(const char* str)
{
  const char* start = str;
  WINPR_ASSERT(str);

  while (*start)
  {
    if (*start == '#' || *start == '?' || *start == '*' || *start == '!' || *start == '%')
    {
      return start;
    }
    start++;
  }
  return nullptr;
}

/** @return TRUE if the descriptor is for an entry inside a copied folder (its name contains a
 *  '\\'), FALSE for a top level file or folder */
WINPR_ATTR_NODISCARD
static BOOL descriptor_is_nested(const FILEDESCRIPTORW* dsc)
{
  WINPR_ASSERT(dsc);

  union
  {
    char c[2];
    WCHAR w;
  } backslash;
  backslash.c[0] = '\\';
  backslash.c[1] = '\0';

  /* only search the name: what follows its '\0' in cFileName is not guaranteed to be zeroed */
  const size_t len = _wcsnlen(dsc->cFileName, ARRAYSIZE(dsc->cFileName));
  return winpr_wcsnchr(dsc->cFileName, len, backslash.w) != nullptr;
}

/* The universal converter from filedescriptors to different file lists */
WINPR_ATTR_MALLOC(free, 1)
static void* convert_filedescriptors_to_file_list(wClipboard* clipboard, const void* data,
                                                  UINT32* pSize, const char* header,
                                                  const char* lineprefix, const char* lineending,
                                                  BOOL skip_last_lineending)
{
  UINT32 nrDescriptors = 0;
  size_t baseLength = 0;
  size_t header_len = strlen(header);
  size_t lineprefix_len = strlen(lineprefix);
  size_t lineending_len = strlen(lineending);

  if (!clipboard || !data || !pSize)
    return nullptr;

  if (*pSize < sizeof(UINT32))
    return nullptr;

  if (clipboard->delegate.basePath)
    baseLength = strnlen(clipboard->delegate.basePath, MAX_PATH);

  if (baseLength < 1)
    return nullptr;

  wStream sbuffer = WINPR_C_ARRAY_INIT;
  wStream* s = Stream_StaticConstInit(&sbuffer, data, *pSize);
  if (!Stream_CheckAndLogRequiredLength(TAG, s, 4))
    return nullptr;

  Stream_Read_UINT32(s, nrDescriptors);

  const size_t count = (*pSize - 4) / sizeof(FILEDESCRIPTORW);

  if ((count < 1) || (count != nrDescriptors))
    return nullptr;

  const FILEDESCRIPTORW* descriptors = Stream_ConstPointer(s);

  /* formatId is the destination format (see ClipboardRegisterSynthesizerEx), the descriptors
   * are the source data */
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
    return nullptr;

  /* Plus 1 for '/' between basepath and filename*/
  const size_t decoration_len = lineprefix_len + lineending_len + baseLength + 1;
  size_t alloc = header_len;

  /* Get total size of file/folder names under first level folder only */
  for (size_t x = 0; x < count; x++)
  {
    const FILEDESCRIPTORW* dsc = &descriptors[x];

    if (!descriptor_is_nested(dsc))
    {
      alloc += ARRAYSIZE(dsc->cFileName) *
               8; /* Overallocate, just take the biggest value the result path can have */
                  /* # (1 char) -> %23 (3 chars) , the first char is replaced inplace */
      alloc += count_special_chars(dsc->cFileName, ARRAYSIZE(dsc->cFileName)) * sizeof(WCHAR);
      alloc += decoration_len;
    }
  }

  /* Append a prefix file:// and postfix \n for each file */
  /* We need to keep last \n since snprintf is null terminated!!  */
  alloc++;
  char* dst = calloc(alloc, sizeof(char));

  if (!dst)
    return nullptr;

  (void)_snprintf(&dst[0], alloc, "%s", header);

  size_t pos = header_len;

  for (size_t x = 0; x < count; x++)
  {
    const FILEDESCRIPTORW* dsc = &descriptors[x];
    BOOL fail = TRUE;
    if (descriptor_is_nested(dsc))
    {
      continue;
    }
    int rc = -1;
    char curName[520] = WINPR_C_ARRAY_INIT;
    const char* stop_at = nullptr;
    const char* previous_at = nullptr;

    if (ConvertWCharNToUtf8(dsc->cFileName, ARRAYSIZE(dsc->cFileName), curName,
                            ARRAYSIZE(curName)) < 0)
      goto loop_fail;

    rc = _snprintf(&dst[pos], alloc - pos, "%s%s/", lineprefix, clipboard->delegate.basePath);

    if (rc < 0)
      goto loop_fail;

    pos += (size_t)rc;

    previous_at = curName;
    while ((stop_at = stop_at_special_chars(previous_at)) != nullptr)
    {
      const intptr_t diff = stop_at - previous_at;
      if (diff < 0)
        goto loop_fail;
      char* tmp = strndup(previous_at, WINPR_ASSERTING_INT_CAST(size_t, diff));
      if (!tmp)
        goto loop_fail;

      rc = _snprintf(&dst[pos], WINPR_ASSERTING_INT_CAST(size_t, diff + 1), "%s", tmp);
      free(tmp);
      if (rc < 0)
        goto loop_fail;

      pos += (size_t)rc;
      rc = _snprintf(&dst[pos], 4, "%%%x", *stop_at);
      if (rc < 0)
        goto loop_fail;

      pos += (size_t)rc;
      previous_at = stop_at + 1;
    }

    rc = _snprintf(&dst[pos], alloc - pos, "%s%s", previous_at, lineending);

    fail = FALSE;
  loop_fail:
    if ((rc < 0) || fail)
    {
      free(dst);
      return nullptr;
    }

    pos += (size_t)rc;
  }

  if (skip_last_lineending)
  {
    const size_t endlen = strlen(lineending);
    if (alloc > endlen)
    {
      const size_t len = strnlen(dst, alloc);
      if (len < endlen)
      {
        free(dst);
        return nullptr;
      }

      if (memcmp(&dst[len - endlen], lineending, endlen) == 0)
      {
        memset(&dst[len - endlen], 0, endlen);
        alloc -= endlen;
      }
    }
  }

  alloc = strnlen(dst, alloc) + 1;
  *pSize = (UINT32)alloc;
  clipboard->fileListSequenceNumber = clipboard->sequenceNumber;
  return dst;
}

/* Prepend header of kde dolphin format to file list
 * See:
 *   GTK: https://docs.gtk.org/glib/struct.Uri.html
 *   uri syntax: https://www.rfc-editor.org/rfc/rfc3986#section-3
 *   uri-lists format: https://www.rfc-editor.org/rfc/rfc2483#section-5
 */
WINPR_ATTR_MALLOC(free, 1)
static void* convert_filedescriptors_to_uri_list(wClipboard* clipboard, UINT32 formatId,
                                                 const void* data, UINT32* pSize)
{
  if (formatId != ClipboardGetFormatId(clipboard, mime_uri_list))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  return convert_filedescriptors_to_file_list(clipboard, data, pSize, "", "file://", "\r\n",
                                              FALSE);
}

/* Prepend header of common gnome format to file list*/
WINPR_ATTR_MALLOC(free, 1)
static void* convert_filedescriptors_to_gnome_copied_files(wClipboard* clipboard, UINT32 formatId,
                                                           const void* data, UINT32* pSize)
{
  if (formatId != ClipboardGetFormatId(clipboard, mime_gnome_copied_files))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  return convert_filedescriptors_to_file_list(clipboard, data, pSize, "copy\n", "file://", "\n",
                                              TRUE);
}

WINPR_ATTR_MALLOC(free, 1)
static void* convert_filedescriptors_to_mate_copied_files(wClipboard* clipboard, UINT32 formatId,
                                                          const void* data, UINT32* pSize)
{
  if (formatId != ClipboardGetFormatId(clipboard, mime_mate_copied_files))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  if (clipboard->formatId != ClipboardGetFormatId(clipboard, mime_FileGroupDescriptorW))
  {
    WLog_ERR(TAG,
             "Unuspported destination format %s [0x%04" PRIx32
             "], trying to convert from %s [0x%04" PRIx32 "]",
             ClipboardGetFormatName(clipboard, formatId), formatId,
             ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId);
    return nullptr;
  }
  char* pDstData = convert_filedescriptors_to_file_list(clipboard, data, pSize, "copy\n",
                                                        "file://", "\n", TRUE);
  if (!pDstData)
  {
    return pDstData;
  }
  /*  Replace last \n with \0
      see
     mate-desktop/caja/libcaja-private/caja-clipboard.c:caja_clipboard_get_uri_list_from_selection_data
  */

  pDstData[*pSize - 1] = '\0';
  *pSize = *pSize - 1;
  return pDstData;
}

static void array_free_synthetic_file(void* the_file)
{
  struct synthetic_file* file = the_file;
  free_synthetic_file(file);
}

static BOOL register_file_formats_and_synthesizers(wClipboard* clipboard)
{
  wObject* obj = nullptr;

  /*
      1. Gnome Nautilus based file manager (Nautilus only with version >= 3.30 AND < 40):
          TARGET: UTF8_STRING
          format: x-special/nautilus-clipboard\copy\n\file://path\n\0
      2. Kde Dolpin and Qt:
          TARGET: text/uri-list
          format: file:path\r\n\0
          See:
            GTK: https://docs.gtk.org/glib/struct.Uri.html
            uri syntax: https://www.rfc-editor.org/rfc/rfc3986#section-3
            uri-lists format: https://www.rfc-editor.org/rfc/rfc2483#section-5
      3. Gnome and others (Unity/XFCE/Nautilus < 3.30/Nautilus >= 40):
          TARGET: x-special/gnome-copied-files
          format: copy\nfile://path\n\0
      4. Mate Caja:
          TARGET: x-special/mate-copied-files
          format: copy\nfile://path\n

      TODO: other file managers do not use previous targets and formats.
  */

  const UINT32 local_gnome_file_format_id =
      ClipboardRegisterFormat(clipboard, mime_gnome_copied_files);
  const UINT32 local_mate_file_format_id =
      ClipboardRegisterFormat(clipboard, mime_mate_copied_files);
  const UINT32 file_group_format_id =
      ClipboardRegisterFormat(clipboard, mime_FileGroupDescriptorW);
  const UINT32 local_file_format_id = ClipboardRegisterFormat(clipboard, mime_uri_list);

  if (!file_group_format_id || !local_file_format_id || !local_gnome_file_format_id ||
      !local_mate_file_format_id)
    goto error;

  clipboard->localFiles = ArrayList_New(FALSE);

  if (!clipboard->localFiles)
    goto error;

  obj = ArrayList_Object(clipboard->localFiles);
  obj->fnObjectFree = array_free_synthetic_file;

  if (!ClipboardRegisterSynthesizerEx(clipboard, local_file_format_id, file_group_format_id,
                                      convert_uri_list_to_filedescriptors))
    goto error_free_local_files;

  if (!ClipboardRegisterSynthesizerEx(clipboard, file_group_format_id, local_file_format_id,
                                      convert_filedescriptors_to_uri_list))
    goto error_free_local_files;

  if (!ClipboardRegisterSynthesizerEx(clipboard, local_gnome_file_format_id, file_group_format_id,
                                      convert_gnome_copied_files_to_filedescriptors))
    goto error_free_local_files;

  if (!ClipboardRegisterSynthesizerEx(clipboard, file_group_format_id, local_gnome_file_format_id,
                                      convert_filedescriptors_to_gnome_copied_files))
    goto error_free_local_files;

  if (!ClipboardRegisterSynthesizerEx(clipboard, local_mate_file_format_id, file_group_format_id,
                                      convert_mate_copied_files_to_filedescriptors))
    goto error_free_local_files;

  if (!ClipboardRegisterSynthesizerEx(clipboard, file_group_format_id, local_mate_file_format_id,
                                      convert_filedescriptors_to_mate_copied_files))
    goto error_free_local_files;

  return TRUE;
error_free_local_files:
  ArrayList_Free(clipboard->localFiles);
  clipboard->localFiles = nullptr;
error:
  return FALSE;
}

static int32_t file_get_size(const struct synthetic_file* file, UINT64* size)
{
  UINT64 s = 0;

  if (!file || !size)
    return E_INVALIDARG;

  s = file->nFileSizeHigh;
  s <<= 32;
  s |= file->nFileSizeLow;
  *size = s;
  return NO_ERROR;
}

static UINT delegate_file_request_size(wClipboardDelegate* delegate,
                                       const wClipboardFileSizeRequest* request)
{
  UINT64 size = 0;

  if (!delegate || !delegate->clipboard || !request)
    return ERROR_BAD_ARGUMENTS;

  if (delegate->clipboard->sequenceNumber != delegate->clipboard->fileListSequenceNumber)
    return ERROR_INVALID_STATE;

  struct synthetic_file* file =
      ArrayList_GetItem(delegate->clipboard->localFiles, request->listIndex);

  if (!file)
    return ERROR_INDEX_ABSENT;

  const int32_t s = file_get_size(file, &size);
  uint32_t error = 0;
  if (error)
    error = delegate->ClipboardFileSizeFailure(delegate, request, (UINT)s);
  else
    error = delegate->ClipboardFileSizeSuccess(delegate, request, size);

  if (error)
    WLog_WARN(TAG, "failed to report file size result: 0x%08X", error);

  return NO_ERROR;
}

UINT synthetic_file_read_close(struct synthetic_file* file, BOOL force)
{
  if (!file || INVALID_HANDLE_VALUE == file->fd)
    return NO_ERROR;

  /* Always force close the file. Clipboard might open hundreds of files
   * so avoid caching to prevent running out of available file descriptors */
  UINT64 size = 0;
  file_get_size(file, &size);
  if ((file->offset < 0) || ((UINT64)file->offset >= size) || force)
  {
    WLog_VRB(TAG, "close file %p", file->fd);
    if (!CloseHandle(file->fd))
    {
      WLog_WARN(TAG, "failed to close fd %p: %" PRIu32, file->fd, GetLastError());
    }

    file->fd = INVALID_HANDLE_VALUE;
  }

  return NO_ERROR;
}

static UINT file_get_range(struct synthetic_file* file, UINT64 offset, UINT32 size,
                           BYTE** actual_data, UINT32* actual_size)
{
  UINT error = NO_ERROR;
  DWORD dwLow = 0;
  DWORD dwHigh = 0;

  WINPR_ASSERT(file);
  WINPR_ASSERT(actual_data);
  WINPR_ASSERT(actual_size);

  if (INVALID_HANDLE_VALUE == file->fd)
  {
    BY_HANDLE_FILE_INFORMATION FileInfo = WINPR_C_ARRAY_INIT;

    file->fd = CreateFileW(file->local_name, GENERIC_READ, 0, nullptr, OPEN_EXISTING,
                           FILE_ATTRIBUTE_NORMAL, nullptr);
    if (INVALID_HANDLE_VALUE == file->fd)
    {
      char name[MAX_PATH] = WINPR_C_ARRAY_INIT;
      ConvertWCharToUtf8(file->local_name, name, sizeof(name) - 1);
      error = GetLastError();
      WLog_ERR(TAG, "failed to open file %s: 0x%08" PRIx32, name, error);
      return error;
    }

    if (!GetFileInformationByHandle(file->fd, &FileInfo))
    {
      char name[MAX_PATH] = WINPR_C_ARRAY_INIT;
      ConvertWCharToUtf8(file->local_name, name, sizeof(name) - 1);
      (void)CloseHandle(file->fd);
      file->fd = INVALID_HANDLE_VALUE;
      error = GetLastError();
      WLog_ERR(TAG, "Get file [%s] information fail: 0x%08" PRIx32, name, error);
      return error;
    }

    file->offset = 0;
    file->nFileSizeHigh = FileInfo.nFileSizeHigh;
    file->nFileSizeLow = FileInfo.nFileSizeLow;

    /*
    {
        UINT64 s = 0;
        file_get_size(file, &s);
        WLog_DBG(TAG, "open file %d -> %s", file->fd, file->local_name);
        WLog_DBG(TAG, "file %d size: %" PRIu64 " bytes", file->fd, s);
    } //*/
  }

  do
  {
    /*
     * We should avoid seeking when possible as some filesystems (e.g.,
     * an FTP server mapped via FUSE) may not support seeking. We keep
     * an accurate account of the current file offset and do not call
     * lseek() if the client requests file content sequentially.
     */
    if (offset > INT64_MAX)
    {
      WLog_ERR(TAG, "offset [%" PRIu64 "] > INT64_MAX", offset);
      error = ERROR_SEEK;
      break;
    }

    if (file->offset != (INT64)offset)
    {
      WLog_DBG(TAG, "file %p force seeking to %" PRIu64 ", current %" PRId64, file->fd,
               offset, file->offset);

      dwHigh = offset >> 32;
      dwLow = offset & 0xFFFFFFFF;
      if (INVALID_SET_FILE_POINTER == SetFilePointer(file->fd,
                                                     WINPR_ASSERTING_INT_CAST(LONG, dwLow),
                                                     (PLONG)&dwHigh, FILE_BEGIN))
      {
        error = GetLastError();
        break;
      }
    }

    BYTE* buffer = malloc(size);
    if (!buffer)
    {
      error = ERROR_NOT_ENOUGH_MEMORY;
      break;
    }
    if (!ReadFile(file->fd, buffer, size, (LPDWORD)actual_size, nullptr))
    {
      free(buffer);
      error = GetLastError();
      break;
    }

    *actual_data = buffer;
    file->offset += *actual_size;
    WLog_VRB(TAG, "file %p actual read %" PRIu32 " bytes (offset %" PRId64 ")", file->fd,
             *actual_size, file->offset);
  } while (0);

  synthetic_file_read_close(file, TRUE /* (error != NO_ERROR) && (size > 0) */);
  return error;
}

static UINT delegate_file_request_range(wClipboardDelegate* delegate,
                                        const wClipboardFileRangeRequest* request)
{
  UINT error = 0;
  BYTE* data = nullptr;
  UINT32 size = 0;
  UINT64 offset = 0;
  struct synthetic_file* file = nullptr;

  if (!delegate || !delegate->clipboard || !request)
    return ERROR_BAD_ARGUMENTS;

  if (delegate->clipboard->sequenceNumber != delegate->clipboard->fileListSequenceNumber)
    return ERROR_INVALID_STATE;

  file = ArrayList_GetItem(delegate->clipboard->localFiles, request->listIndex);

  if (!file)
    return ERROR_INDEX_ABSENT;

  offset = (((UINT64)request->nPositionHigh) << 32) | ((UINT64)request->nPositionLow);
  error = file_get_range(file, offset, request->cbRequested, &data, &size);

  if (error)
    error = delegate->ClipboardFileRangeFailure(delegate, request, error);
  else
    error = delegate->ClipboardFileRangeSuccess(delegate, request, data, size);

  if (error)
    WLog_WARN(TAG, "failed to report file range result: 0x%08X", error);

  free(data);
  return NO_ERROR;
}

static UINT dummy_file_size_success(WINPR_ATTR_UNUSED wClipboardDelegate* delegate,
                                    WINPR_ATTR_UNUSED const wClipboardFileSizeRequest* request,
                                    WINPR_ATTR_UNUSED UINT64 fileSize)
{
  return ERROR_NOT_SUPPORTED;
}

static UINT dummy_file_size_failure(WINPR_ATTR_UNUSED wClipboardDelegate* delegate,
                                    WINPR_ATTR_UNUSED const wClipboardFileSizeRequest* request,
                                    WINPR_ATTR_UNUSED UINT errorCode)
{
  return ERROR_NOT_SUPPORTED;
}

static UINT dummy_file_range_success(WINPR_ATTR_UNUSED wClipboardDelegate* delegate,
                                     WINPR_ATTR_UNUSED const wClipboardFileRangeRequest* request,
                                     WINPR_ATTR_UNUSED const BYTE* data,
                                     WINPR_ATTR_UNUSED UINT32 size)
{
  return ERROR_NOT_SUPPORTED;
}

static UINT dummy_file_range_failure(WINPR_ATTR_UNUSED wClipboardDelegate* delegate,
                                     WINPR_ATTR_UNUSED const wClipboardFileRangeRequest* request,
                                     WINPR_ATTR_UNUSED UINT errorCode)
{
  return ERROR_NOT_SUPPORTED;
}

static void setup_delegate(wClipboardDelegate* delegate)
{
  WINPR_ASSERT(delegate);

  delegate->ClientRequestFileSize = delegate_file_request_size;
  delegate->ClipboardFileSizeSuccess = dummy_file_size_success;
  delegate->ClipboardFileSizeFailure = dummy_file_size_failure;
  delegate->ClientRequestFileRange = delegate_file_request_range;
  delegate->ClipboardFileRangeSuccess = dummy_file_range_success;
  delegate->ClipboardFileRangeFailure = dummy_file_range_failure;
  delegate->IsFileNameComponentValid = ValidFileNameComponent;
}

BOOL ClipboardInitSyntheticFileSubsystem(wClipboard* clipboard)
{
  if (!clipboard)
    return FALSE;

  if (!register_file_formats_and_synthesizers(clipboard))
    return FALSE;

  setup_delegate(&clipboard->delegate);
  return TRUE;
}

Coverage Report

Created: 2026-10-15 06:30