/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#include <svl/msodocumentlockfile.hxx>
#include <algorithm>
#include <ucbhelper/content.hxx>
#include <comphelper/processfactory.hxx>
#include <o3tl/string_view.hxx>
#include <com/sun/star/io/IOException.hpp>
#include <com/sun/star/io/XOutputStream.hpp>
#include <com/sun/star/io/XInputStream.hpp>
#include <com/sun/star/ucb/XCommandEnvironment.hpp>
namespace svt
{
namespace
{
bool isWordFormat(std::u16string_view sExt)
{
return o3tl::equalsIgnoreAsciiCase(sExt, u"DOC") || o3tl::equalsIgnoreAsciiCase(sExt, u"DOCX")
|| o3tl::equalsIgnoreAsciiCase(sExt, u"RTF")
|| o3tl::equalsIgnoreAsciiCase(sExt, u"ODT");
}
bool isExcelFormat(std::u16string_view sExt)
{
return //sExt.equalsIgnoreAsciiCase("XLS") || // MSO does not create lockfile for XLS
o3tl::equalsIgnoreAsciiCase(sExt, u"XLSX") || o3tl::equalsIgnoreAsciiCase(sExt, u"ODS");
}
bool isPowerPointFormat(std::u16string_view sExt)
{
return o3tl::equalsIgnoreAsciiCase(sExt, u"PPTX") || o3tl::equalsIgnoreAsciiCase(sExt, u"PPT")
|| o3tl::equalsIgnoreAsciiCase(sExt, u"ODP");
}
// Need to generate different lock file name for MSO.
OUString GenerateMSOLockFileURL(std::u16string_view aOrigURL)
{
INetURLObject aURL = LockFileCommon::ResolveLinks(INetURLObject(aOrigURL));
// For text documents MSO Word cuts some of the first characters of the file name
OUString sFileName = aURL.GetLastName();
const OUString sExt = aURL.GetFileExtension();
if (isWordFormat(sExt))
{
const sal_Int32 nFileNameLength = sFileName.getLength() - sExt.getLength() - 1;
if (nFileNameLength >= 8)
sFileName = sFileName.copy(2);
else if (nFileNameLength == 7)
sFileName = sFileName.copy(1);
}
aURL.setName(Concat2View("~$" + sFileName));
return aURL.GetMainURL(INetURLObject::DecodeMechanism::NONE);
}
}
// static
MSODocumentLockFile::AppType MSODocumentLockFile::getAppType(std::u16string_view sOrigURL)
{
AppType eResult = AppType::PowerPoint;
INetURLObject aDocURL = LockFileCommon::ResolveLinks(INetURLObject(sOrigURL));
const OUString sExt = aDocURL.GetFileExtension();
if (isWordFormat(sExt))
eResult = AppType::Word;
else if (isExcelFormat(sExt))
eResult = AppType::Excel;
return eResult;
}
MSODocumentLockFile::MSODocumentLockFile(std::u16string_view aOrigURL)
: GenDocumentLockFile(GenerateMSOLockFileURL(aOrigURL))
, m_eAppType(getAppType(aOrigURL))
{
}
MSODocumentLockFile::~MSODocumentLockFile() {}
void MSODocumentLockFile::WriteEntryToStream(
std::unique_lock<std::mutex>& /*rGuard*/, const LockFileEntry& aEntry,
const css::uno::Reference<css::io::XOutputStream>& xOutput)
{
// Reallocate the date with the right size, different lock file size for different components
int nLockFileSize = m_eAppType == AppType::Word ? MSO_WORD_LOCKFILE_SIZE
: MSO_EXCEL_AND_POWERPOINT_LOCKFILE_SIZE;
css::uno::Sequence<sal_Int8> aData(nLockFileSize);
auto pData = aData.getArray();
// Write out the user name's length as a single byte integer
// The maximum length is 52 in MSO, so we'll need to truncate the user name if it's longer
OUString aUserName = aEntry[LockFileComponent::OOOUSERNAME];
int nIndex = 0;
pData[nIndex] = static_cast<sal_Int8>(
std::min(aUserName.getLength(), sal_Int32(MSO_USERNAME_MAX_LENGTH)));
if (aUserName.getLength() > MSO_USERNAME_MAX_LENGTH)
aUserName = aUserName.copy(0, MSO_USERNAME_MAX_LENGTH);
// From the second position write out the user name using one byte characters.
nIndex = 1;
for (int nChar = 0; nChar < aUserName.getLength(); ++nChar)
{
pData[nIndex] = static_cast<sal_Int8>(aUserName[nChar]);
++nIndex;
}
// Fill up the remaining bytes with dummy data
switch (m_eAppType)
{
case AppType::Word:
while (nIndex < MSO_USERNAME_MAX_LENGTH + 2)
{
pData[nIndex] = static_cast<sal_Int8>(0);
++nIndex;
}
break;
case AppType::PowerPoint:
pData[nIndex] = static_cast<sal_Int8>(0);
++nIndex;
[[fallthrough]];
case AppType::Excel:
while (nIndex < MSO_USERNAME_MAX_LENGTH + 3)
{
pData[nIndex] = static_cast<sal_Int8>(0x20);
++nIndex;
}
break;
}
// At the next position we have the user name's length again, but now as a 2 byte integer
pData[nIndex] = static_cast<sal_Int8>(
std::min(aUserName.getLength(), sal_Int32(MSO_USERNAME_MAX_LENGTH)));
++nIndex;
pData[nIndex] = 0;
++nIndex;
// And the user name again with unicode characters
for (int nChar = 0; nChar < aUserName.getLength(); ++nChar)
{
pData[nIndex] = static_cast<sal_Int8>(aUserName[nChar] & 0xff);
++nIndex;
pData[nIndex] = static_cast<sal_Int8>(aUserName[nChar] >> 8);
++nIndex;
}
// Fill the remaining part with dummy bits
switch (m_eAppType)
{
case AppType::Word:
while (nIndex < nLockFileSize)
{
pData[nIndex] = static_cast<sal_Int8>(0);
++nIndex;
}
break;
case AppType::Excel:
case AppType::PowerPoint:
while (nIndex < nLockFileSize)
{
pData[nIndex] = static_cast<sal_Int8>(0x20);
++nIndex;
if (nIndex < nLockFileSize)
{
pData[nIndex] = static_cast<sal_Int8>(0);
++nIndex;
}
}
break;
}
xOutput->writeBytes(aData);
}
css::uno::Reference<css::io::XInputStream>
MSODocumentLockFile::OpenStream(std::unique_lock<std::mutex>& /*rGuard*/)
{
css::uno::Reference<css::ucb::XCommandEnvironment> xEnv;
::ucbhelper::Content aSourceContent(GetURL(), xEnv, comphelper::getProcessComponentContext());
// the file can be opened readonly, no locking will be done
return aSourceContent.openStreamNoLock();
}
LockFileEntry MSODocumentLockFile::GetLockDataImpl(std::unique_lock<std::mutex>& rGuard)
{
LockFileEntry aResult;
css::uno::Reference<css::io::XInputStream> xInput = OpenStream(rGuard);
if (!xInput.is())
throw css::uno::RuntimeException();
const sal_Int32 nBufLen = 256;
css::uno::Sequence<sal_Int8> aBuf(nBufLen);
const sal_Int32 nRead = xInput->readBytes(aBuf, nBufLen);
xInput->closeInput();
if (nRead >= 162)
{
// Reverse engineering of MS Office Owner Files format (MS Office 2016 tested).
// It starts with a single byte with name length, after which characters of username go
// in current Windows 8-bit codepage.
// For Word lockfiles, the name is followed by zero bytes up to position 54.
// For PowerPoint lockfiles, the name is followed by a single zero byte, and then 0x20
// bytes up to position 55.
// For Excel lockfiles, the name is followed by 0x20 bytes up to position 55.
// At those positions in each type of lockfile, a name length 2-byte word goes, followed
// by UTF-16-LE-encoded copy of username. Spaces or some garbage follow up to the end of
// the lockfile (total 162 bytes for Word, 165 bytes for Excel/PowerPoint).
// Apparently MS Office does not allow username to be longer than 52 characters (trying
// to enter more in its options dialog results in error messages stating this limit).
const int nACPLen = aBuf[0];
if (nACPLen > 0 && nACPLen <= 52) // skip wrong format
{
const sal_Int8* pBuf = aBuf.getConstArray() + 54;
int nUTF16Len = *pBuf; // try Word position
// If UTF-16 length is 0x20, then ACP length is also less than maximal, which means
// that in Word lockfile case, at least two preceding bytes would be zero. Both
// Excel and PowerPoint lockfiles would have at least one of those bytes non-zero.
if (nUTF16Len == 0x20 && (*(pBuf - 1) != 0 || *(pBuf - 2) != 0))
nUTF16Len = *++pBuf; // use Excel/PowerPoint position
if (nUTF16Len > 0 && nUTF16Len <= 52) // skip wrong format
{
OUStringBuffer str(nUTF16Len);
sal_uInt8 const* p = reinterpret_cast<sal_uInt8 const*>(pBuf + 2);
for (int i = 0; i != nUTF16Len; ++i)
{
str.append(sal_Unicode(p[0] | (sal_uInt32(p[1]) << 8)));
p += 2;
}
aResult[LockFileComponent::OOOUSERNAME] = str.makeStringAndClear();
}
}
}
return aResult;
}
void MSODocumentLockFile::RemoveFile()
{
std::unique_lock aGuard(m_aMutex);
// TODO/LATER: the removing is not atomic, is it possible in general to make it atomic?
LockFileEntry aNewEntry = GenerateOwnEntry();
LockFileEntry aFileData = GetLockDataImpl(aGuard);
if (aFileData[LockFileComponent::OOOUSERNAME] != aNewEntry[LockFileComponent::OOOUSERNAME])
throw css::io::IOException(); // not the owner, access denied
RemoveFileDirectly();
}
bool MSODocumentLockFile::IsMSOSupportedFileFormat(std::u16string_view aURL)
{
INetURLObject aDocURL = LockFileCommon::ResolveLinks(INetURLObject(aURL));
const OUString sExt = aDocURL.GetFileExtension();
return isWordFormat(sExt) || isExcelFormat(sExt) || isPowerPointFormat(sExt);
}
} // namespace svt
/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
↑ V530 The return value of function 'append' is required to be utilized.