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

Source
/**
 * WinPR: Windows Portable Runtime
 * Clipboard Functions
 *
 * Copyright 2014 Marc-Andre Moreau <marcandre.moreau@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/crt.h>
#include <winpr/collections.h>
#include <winpr/wlog.h>

#include <winpr/clipboard.h>

#include "clipboard.h"

#include "synthetic_file.h"

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

const char* const mime_text_plain = "text/plain";
const char* const mime_text_utf8 = "text/plain;charset=utf-8";
const char* const mime_text_UTF8_STRING = "UTF8_STRING";

/**
 * Clipboard (Windows):
 * msdn.microsoft.com/en-us/library/windows/desktop/ms648709/
 *
 * W3C Clipboard API and events:
 * http://www.w3.org/TR/clipboard-apis/
 */

static const char* CF_STANDARD_STRINGS[] = {
  "CF_RAW",          /* 0 */
  "CF_TEXT",         /* 1 */
  "CF_BITMAP",       /* 2 */
  "CF_METAFILEPICT", /* 3 */
  "CF_SYLK",         /* 4 */
  "CF_DIF",          /* 5 */
  "CF_TIFF",         /* 6 */
  "CF_OEMTEXT",      /* 7 */
  "CF_DIB",          /* 8 */
  "CF_PALETTE",      /* 9 */
  "CF_PENDATA",      /* 10 */
  "CF_RIFF",         /* 11 */
  "CF_WAVE",         /* 12 */
  "CF_UNICODETEXT",  /* 13 */
  "CF_ENHMETAFILE",  /* 14 */
  "CF_HDROP",        /* 15 */
  "CF_LOCALE",       /* 16 */
  "CF_DIBV5"         /* 17 */
};

const char* ClipboardGetFormatIdString(UINT32 formatId)
{
  if (formatId < ARRAYSIZE(CF_STANDARD_STRINGS))
    return CF_STANDARD_STRINGS[formatId];
  return "CF_REGISTERED_FORMAT";
}

static wClipboardFormat* ClipboardFindFormat(wClipboard* clipboard, UINT32 formatId,
                                             const char* name)
{
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return nullptr;

  if (formatId)
  {
    for (UINT32 index = 0; index < clipboard->numFormats; index++)
    {
      wClipboardFormat* cformat = &clipboard->formats[index];
      if (formatId == cformat->formatId)
      {
        format = cformat;
        break;
      }
    }
  }
  else if (name)
  {
    for (UINT32 index = 0; index < clipboard->numFormats; index++)
    {
      wClipboardFormat* cformat = &clipboard->formats[index];
      if (!cformat->formatName)
        continue;

      if (strcmp(name, cformat->formatName) == 0)
      {
        format = cformat;
        break;
      }
    }
  }
  else
  {
    /* special "CF_RAW" case */
    if (clipboard->numFormats > 0)
    {
      format = &clipboard->formats[0];

      if (format->formatId)
        return nullptr;

      if (!format->formatName || (strcmp(format->formatName, CF_STANDARD_STRINGS[0]) == 0))
        return format;
    }
  }

  return format;
}

static wClipboardSynthesizer* ClipboardFindSynthesizer(wClipboardFormat* format, UINT32 formatId)
{
  if (!format)
    return nullptr;

  for (UINT32 index = 0; index < format->numSynthesizers; index++)
  {
    wClipboardSynthesizer* synthesizer = &(format->synthesizers[index]);

    if (formatId == synthesizer->syntheticId)
      return synthesizer;
  }

  return nullptr;
}

void ClipboardLock(wClipboard* clipboard)
{
  if (!clipboard)
    return;

  EnterCriticalSection(&(clipboard->lock));
}

void ClipboardUnlock(wClipboard* clipboard)
{
  if (!clipboard)
    return;

  LeaveCriticalSection(&(clipboard->lock));
}

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

  if (clipboard->data)
  {
    free(clipboard->data);
    clipboard->data = nullptr;
  }

  clipboard->size = 0;
  clipboard->formatId = 0;
  clipboard->sequenceNumber++;
  return TRUE;
}

UINT32 ClipboardCountRegisteredFormats(wClipboard* clipboard)
{
  if (!clipboard)
    return 0;

  return clipboard->numFormats;
}

UINT32 ClipboardGetRegisteredFormatIds(wClipboard* clipboard, UINT32** ppFormatIds)
{
  UINT32* pFormatIds = nullptr;
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return 0;

  if (!ppFormatIds)
    return 0;

  pFormatIds = *ppFormatIds;

  if (!pFormatIds)
  {
    pFormatIds = calloc(clipboard->numFormats, sizeof(UINT32));

    if (!pFormatIds)
      return 0;

    *ppFormatIds = pFormatIds;
  }

  for (UINT32 index = 0; index < clipboard->numFormats; index++)
  {
    format = &(clipboard->formats[index]);
    pFormatIds[index] = format->formatId;
  }

  return clipboard->numFormats;
}

UINT32 ClipboardRegisterFormat(wClipboard* clipboard, const char* name)
{
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return 0;

  format = ClipboardFindFormat(clipboard, 0, name);

  if (format)
    return format->formatId;

  if ((clipboard->numFormats + 1) >= clipboard->maxFormats)
  {
    UINT32 numFormats = clipboard->maxFormats * 2;
    wClipboardFormat* tmpFormat = nullptr;
    tmpFormat =
        (wClipboardFormat*)realloc(clipboard->formats, numFormats * sizeof(wClipboardFormat));

    if (!tmpFormat)
      return 0;

    clipboard->formats = tmpFormat;
    clipboard->maxFormats = numFormats;
  }

  format = &(clipboard->formats[clipboard->numFormats]);
  ZeroMemory(format, sizeof(wClipboardFormat));

  if (name)
  {
    format->formatName = _strdup(name);

    if (!format->formatName)
      return 0;
  }

  format->formatId = clipboard->nextFormatId++;
  clipboard->numFormats++;
  return format->formatId;
}

WINPR_ATTR_NODISCARD
static wClipboardSynthesizer* registerSynthesizer(wClipboard* clipboard, UINT32 formatId,
                                                  UINT32 syntheticId)
{
  if (!clipboard)
  {
    WLog_WARN(TAG,
              "Failed to register synthesizer for %s[0x%04" PRIx32 "] to %s [0x%04" PRIx32
              "]: clipboard=NULL",
              ClipboardGetFormatName(clipboard, formatId), formatId,
              ClipboardGetFormatName(clipboard, syntheticId), syntheticId);
    return nullptr;
  }

  WLog_DBG(TAG, "Registering synthesizer for %s[0x%04" PRIx32 "] to %s [0x%04" PRIx32 "]",
           ClipboardGetFormatName(clipboard, formatId), formatId,
           ClipboardGetFormatName(clipboard, syntheticId), syntheticId);

  wClipboardFormat* format = ClipboardFindFormat(clipboard, formatId, nullptr);

  if (!format)
  {
    WLog_WARN(TAG,
              "Failed to register synthesizer for %s[0x%04" PRIx32 "] to %s [0x%04" PRIx32
              "]: format=NULL",
              ClipboardGetFormatName(clipboard, formatId), formatId,
              ClipboardGetFormatName(clipboard, syntheticId), syntheticId);
    return nullptr;
  }

  if (format->formatId == syntheticId)
  {
    WLog_WARN(TAG,
              "Failed to register synthesizer for %s[0x%04" PRIx32 "] to %s [0x%04" PRIx32
              "]: formats equal",
              ClipboardGetFormatName(clipboard, formatId), formatId,
              ClipboardGetFormatName(clipboard, syntheticId), syntheticId);
    return nullptr;
  }

  wClipboardSynthesizer* synthesizer = ClipboardFindSynthesizer(format, formatId);

  if (!synthesizer)
  {
    UINT32 numSynthesizers = format->numSynthesizers + 1;
    wClipboardSynthesizer* tmpSynthesizer = (wClipboardSynthesizer*)realloc(
        format->synthesizers, numSynthesizers * sizeof(wClipboardSynthesizer));

    if (!tmpSynthesizer)
    {
      WLog_WARN(TAG,
                "Failed to register synthesizer for %s[0x%04" PRIx32 "] to %s [0x%04" PRIx32
                "]: failed to allocate new synthesizer",
                ClipboardGetFormatName(clipboard, formatId), formatId,
                ClipboardGetFormatName(clipboard, syntheticId), syntheticId);
      return nullptr;
    }

    format->synthesizers = tmpSynthesizer;
    format->numSynthesizers = numSynthesizers;
    const UINT32 index = numSynthesizers - 1;
    synthesizer = &(format->synthesizers[index]);
  }
  return synthesizer;
}

BOOL ClipboardRegisterSynthesizer(wClipboard* clipboard, UINT32 formatId, UINT32 syntheticId,
                                  CLIPBOARD_SYNTHESIZE_FN pfnSynthesize)
{
  wClipboardSynthesizer* synthesizer = registerSynthesizer(clipboard, formatId, syntheticId);
  if (!synthesizer)
    return FALSE;

  synthesizer->syntheticId = syntheticId;
  synthesizer->pfnSynthesize = pfnSynthesize;
  return TRUE;
}

BOOL ClipboardRegisterSynthesizerEx(wClipboard* clipboard, UINT32 formatId, UINT32 syntheticId,
                                    CLIPBOARD_SYNTHESIZE_FN pfnSynthesize)
{
  wClipboardSynthesizer* synthesizer = registerSynthesizer(clipboard, formatId, syntheticId);
  if (!synthesizer)
    return FALSE;

  synthesizer->syntheticId = syntheticId;
  synthesizer->pfnSynthesizeEx = pfnSynthesize;
  return TRUE;
}

UINT32 ClipboardCountFormats(wClipboard* clipboard)
{
  UINT32 count = 0;
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return 0;

  format = ClipboardFindFormat(clipboard, clipboard->formatId, nullptr);

  if (!format)
    return 0;

  count = 1 + format->numSynthesizers;
  return count;
}

UINT32 ClipboardGetFormatIds(wClipboard* clipboard, UINT32** ppFormatIds)
{
  UINT32 count = 0;
  UINT32* pFormatIds = nullptr;
  wClipboardFormat* format = nullptr;
  wClipboardSynthesizer* synthesizer = nullptr;

  if (!clipboard)
    return 0;

  format = ClipboardFindFormat(clipboard, clipboard->formatId, nullptr);

  if (!format)
    return 0;

  count = 1 + format->numSynthesizers;

  if (!ppFormatIds)
    return 0;

  pFormatIds = *ppFormatIds;

  if (!pFormatIds)
  {
    pFormatIds = calloc(count, sizeof(UINT32));

    if (!pFormatIds)
      return 0;

    *ppFormatIds = pFormatIds;
  }

  pFormatIds[0] = format->formatId;

  for (UINT32 index = 1; index < count; index++)
  {
    synthesizer = &(format->synthesizers[index - 1]);
    pFormatIds[index] = synthesizer->syntheticId;
  }

  return count;
}

static void ClipboardUninitFormats(wClipboard* clipboard)
{
  WINPR_ASSERT(clipboard);
  for (UINT32 formatId = 0; formatId < clipboard->numFormats; formatId++)
  {
    wClipboardFormat* format = &clipboard->formats[formatId];
    free(format->formatName);
    free(format->synthesizers);
    format->formatName = nullptr;
    format->synthesizers = nullptr;
  }
}

static BOOL ClipboardInitFormats(wClipboard* clipboard)
{
  UINT32 formatId = 0;
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return FALSE;

  for (formatId = 0; formatId < CF_MAX; formatId++, clipboard->numFormats++)
  {
    format = &(clipboard->formats[clipboard->numFormats]);
    ZeroMemory(format, sizeof(wClipboardFormat));
    format->formatId = formatId;
    format->formatName = _strdup(CF_STANDARD_STRINGS[formatId]);

    if (!format->formatName)
      goto error;
  }

  if (!ClipboardInitSynthesizers(clipboard))
    goto error;

  return TRUE;
error:

  ClipboardUninitFormats(clipboard);
  return FALSE;
}

UINT32 ClipboardGetFormatId(wClipboard* clipboard, const char* name)
{
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return 0;

  format = ClipboardFindFormat(clipboard, 0, name);

  if (!format)
    return 0;

  return format->formatId;
}

const char* ClipboardGetFormatName(wClipboard* clipboard, UINT32 formatId)
{
  wClipboardFormat* format = nullptr;

  if (!clipboard)
    return nullptr;

  format = ClipboardFindFormat(clipboard, formatId, nullptr);

  if (!format)
    return nullptr;

  return format->formatName;
}

void* ClipboardGetData(wClipboard* clipboard, UINT32 formatId, UINT32* pSize)
{
  void* pDstData = nullptr;

  if (!clipboard || !pSize)
  {
    WLog_ERR(TAG, "Invalid parameters clipboard=%p, pSize=%p",
             WINPR_CXX_COMPAT_CAST(const void*, clipboard),
             WINPR_CXX_COMPAT_CAST(const void*, pSize));
    return nullptr;
  }

  *pSize = 0;
  wClipboardFormat* format = ClipboardFindFormat(clipboard, clipboard->formatId, nullptr);

  if (!format)
  {
    WLog_ERR(TAG, "Format [0x%08" PRIx32 "] not found", clipboard->formatId);
    return nullptr;
  }

  const UINT32 SrcSize = clipboard->size;
  void* pSrcData = clipboard->data;

  if (formatId == format->formatId)
  {
    UINT32 DstSize = SrcSize;
    pDstData = malloc(DstSize);

    if (!pDstData)
      return nullptr;

    CopyMemory(pDstData, pSrcData, SrcSize);
    *pSize = DstSize;
  }
  else
  {
    wClipboardSynthesizer* synthesizer = ClipboardFindSynthesizer(format, formatId);

    if (!synthesizer || !(synthesizer->pfnSynthesize || synthesizer->pfnSynthesizeEx))
    {
      WLog_ERR(TAG, "No synthesizer for format %s [0x%08" PRIx32 "] --> %s [0x%08" PRIx32 "]",
               ClipboardGetFormatName(clipboard, clipboard->formatId), clipboard->formatId,
               ClipboardGetFormatName(clipboard, formatId), formatId);
      return nullptr;
    }

    UINT32 DstSize = SrcSize;
    if (synthesizer->pfnSynthesizeEx)
      pDstData = synthesizer->pfnSynthesizeEx(clipboard, synthesizer->syntheticId, pSrcData,
                                              &DstSize);
    else
      pDstData = synthesizer->pfnSynthesize(clipboard, format->formatId, pSrcData, &DstSize);
    if (pDstData)
      *pSize = DstSize;
  }

  WLog_DBG(TAG, "getting formatId=%s [0x%08" PRIx32 "] data=%p, size=%" PRIu32,
           ClipboardGetFormatName(clipboard, formatId), formatId, pDstData, *pSize);
  return pDstData;
}

BOOL ClipboardSetData(wClipboard* clipboard, UINT32 formatId, const void* data, UINT32 size)
{
  wClipboardFormat* format = nullptr;

  WLog_DBG(TAG, "setting formatId=%s [0x%08" PRIx32 "], size=%" PRIu32,
           ClipboardGetFormatName(clipboard, formatId), formatId, size);
  if (!clipboard)
    return FALSE;

  format = ClipboardFindFormat(clipboard, formatId, nullptr);

  if (!format)
    return FALSE;

  free(clipboard->data);

  /* append 2 WCHAR zero bytes. Prevent problems with odd input data sizes. */
  clipboard->data = calloc(size + 2ull * sizeof(WCHAR), sizeof(char));

  if (!clipboard->data)
    return FALSE;

  memcpy(clipboard->data, data, size);

  /* For string values we don´t know if they are '\0' terminated.
   * so set the size to the full length in bytes (e.g. string length + 1)
   */
  switch (formatId)
  {
    case CF_TEXT:
    case CF_OEMTEXT:
      clipboard->size = (UINT32)(strnlen(clipboard->data, size) + 1UL);
      break;
    case CF_UNICODETEXT:
      clipboard->size =
          (UINT32)((_wcsnlen(clipboard->data, size / sizeof(WCHAR)) + 1UL) * sizeof(WCHAR));
      break;
    default:
      clipboard->size = size;
      break;
  }

  clipboard->formatId = formatId;
  clipboard->sequenceNumber++;
  return TRUE;
}

UINT64 ClipboardGetOwner(wClipboard* clipboard)
{
  if (!clipboard)
    return 0;

  return clipboard->ownerId;
}

void ClipboardSetOwner(wClipboard* clipboard, UINT64 ownerId)
{
  if (!clipboard)
    return;

  clipboard->ownerId = ownerId;
}

wClipboardDelegate* ClipboardGetDelegate(wClipboard* clipboard)
{
  if (!clipboard)
    return nullptr;

  return &clipboard->delegate;
}

static void ClipboardInitLocalFileSubsystem(wClipboard* clipboard)
{
  /*
   * There can be only one local file subsystem active.
   * Return as soon as initialization succeeds.
   */
  if (ClipboardInitSyntheticFileSubsystem(clipboard))
  {
    WLog_DBG(TAG, "initialized synthetic local file subsystem");
    return;
  }
  else
  {
    WLog_WARN(TAG, "failed to initialize synthetic local file subsystem");
  }

  WLog_INFO(TAG, "failed to initialize local file subsystem, file transfer not available");
}

wClipboard* ClipboardCreate(void)
{
  wClipboard* clipboard = (wClipboard*)calloc(1, sizeof(wClipboard));

  if (!clipboard)
    return nullptr;

  clipboard->nextFormatId = 0xC000;
  clipboard->sequenceNumber = 0;

  if (!InitializeCriticalSectionAndSpinCount(&(clipboard->lock), 4000))
    goto fail;

  clipboard->numFormats = 0;
  clipboard->maxFormats = 64;
  clipboard->formats = (wClipboardFormat*)calloc(clipboard->maxFormats, sizeof(wClipboardFormat));

  if (!clipboard->formats)
    goto fail;

  if (!ClipboardInitFormats(clipboard))
    goto fail;

  clipboard->delegate.clipboard = clipboard;
  ClipboardInitLocalFileSubsystem(clipboard);
  return clipboard;
fail:
  ClipboardDestroy(clipboard);
  return nullptr;
}

void ClipboardDestroy(wClipboard* clipboard)
{
  if (!clipboard)
    return;

  ArrayList_Free(clipboard->localFiles);
  clipboard->localFiles = nullptr;

  ClipboardUninitFormats(clipboard);

  free(clipboard->data);
  clipboard->data = nullptr;
  clipboard->size = 0;
  clipboard->numFormats = 0;
  free(clipboard->formats);
  DeleteCriticalSection(&(clipboard->lock));
  free(clipboard);
}

static BOOL is_dos_drive(const char* path, size_t len)
{
  if (len < 2)
    return FALSE;

  WINPR_ASSERT(path);
  if (path[1] == ':' || path[1] == '|')
  {
    if (((path[0] >= 'A') && (path[0] <= 'Z')) || ((path[0] >= 'a') && (path[0] <= 'z')))
      return TRUE;
  }
  return FALSE;
}

char* parse_uri_to_local_file(const char* uri, size_t uri_len)
{
  // URI is specified by RFC 8089: https://datatracker.ietf.org/doc/html/rfc8089
  const char prefix[] = "file:";
  const char prefixTraditional[] = "file://";
  const char* localName = nullptr;
  size_t localLen = 0;
  char* buffer = nullptr;
  const size_t prefixLen = strnlen(prefix, sizeof(prefix));
  const size_t prefixTraditionalLen = strnlen(prefixTraditional, sizeof(prefixTraditional));

  WINPR_ASSERT(uri || (uri_len == 0));

  WLog_VRB(TAG, "processing URI: %.*s", WINPR_ASSERTING_INT_CAST(int, uri_len), uri);

  if ((uri_len <= prefixLen) || strncmp(uri, prefix, prefixLen) != 0)
  {
    WLog_ERR(TAG, "non-'file:' URI schemes are not supported");
    return nullptr;
  }

  do
  {
    /* https://datatracker.ietf.org/doc/html/rfc8089#appendix-F
     * - The minimal representation of a local file in a DOS- or Windows-
     *   based environment with no authority field and an absolute path
     *   that begins with a drive letter.
     *
     *   "file:c:/path/to/file"
     *
     * - Regular DOS or Windows file URIs with vertical line characters in
     *   the drive letter construct.
     *
     *   "file:c|/path/to/file"
     *
     */
    if (uri[prefixLen] != '/')
    {

      if (is_dos_drive(&uri[prefixLen], uri_len - prefixLen))
      {
        // Dos and Windows file URI
        localName = &uri[prefixLen];
        localLen = uri_len - prefixLen;
        break;
      }
      else
      {
        WLog_ERR(TAG, "URI format are not supported: %s", uri);
        return nullptr;
      }
    }

    /*
     * - The minimal representation of a local file with no authority field
     *   and an absolute path that begins with a slash "/".  For example:
     *
     *   "file:/path/to/file"
     *
     */
    else if ((uri_len > prefixLen + 1) && (uri[prefixLen + 1] != '/'))
    {
      if (is_dos_drive(&uri[prefixLen + 1], uri_len - prefixLen - 1))
      {
        // Dos and Windows file URI
        localName = (uri + prefixLen + 1);
        localLen = uri_len - prefixLen - 1;
      }
      else
      {
        localName = &uri[prefixLen];
        localLen = uri_len - prefixLen;
      }
      break;
    }

    /*
     * - A traditional file URI for a local file with an empty authority.
     *
     *   "file:///path/to/file"
     */
    if ((uri_len < prefixTraditionalLen) ||
        strncmp(uri, prefixTraditional, prefixTraditionalLen) != 0)
    {
      WLog_ERR(TAG, "non-'file:' URI schemes are not supported");
      return nullptr;
    }

    localName = &uri[prefixTraditionalLen];
    localLen = uri_len - prefixTraditionalLen;

    if (localLen < 1)
    {
      WLog_ERR(TAG, "empty 'file:' URI schemes are not supported");
      return nullptr;
    }

    /*
     * "file:///c:/path/to/file"
     * "file:///c|/path/to/file"
     */
    if (localName[0] != '/')
    {
      WLog_ERR(TAG, "URI format are not supported: %s", uri);
      return nullptr;
    }

    if (is_dos_drive(&localName[1], localLen - 1))
    {
      localName++;
      localLen--;
    }

  } while (0);

  buffer = winpr_str_url_decode(localName, localLen);
  if (buffer)
  {
    if (buffer[1] == '|' &&
        ((buffer[0] >= 'A' && buffer[0] <= 'Z') || (buffer[0] >= 'a' && buffer[0] <= 'z')))
      buffer[1] = ':';
    return buffer;
  }

  return nullptr;
}

Coverage Report

Created: 2026-10-15 06:27