QuietUnrar/Carthage/Checkouts/UnrarKit/Libraries/unrar/win32lnk.cpp

175 lines
5.8 KiB
C++

#define SYMLINK_FLAG_RELATIVE 1
typedef struct _REPARSE_DATA_BUFFER {
ULONG ReparseTag;
USHORT ReparseDataLength;
USHORT Reserved;
union {
struct {
USHORT SubstituteNameOffset;
USHORT SubstituteNameLength;
USHORT PrintNameOffset;
USHORT PrintNameLength;
ULONG Flags;
WCHAR PathBuffer[1];
} SymbolicLinkReparseBuffer;
struct {
USHORT SubstituteNameOffset;
USHORT SubstituteNameLength;
USHORT PrintNameOffset;
USHORT PrintNameLength;
WCHAR PathBuffer[1];
} MountPointReparseBuffer;
struct {
UCHAR DataBuffer[1];
} GenericReparseBuffer;
};
} REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
bool CreateReparsePoint(CommandData *Cmd,const wchar *Name,FileHeader *hd)
{
static bool PrivSet=false;
if (!PrivSet)
{
SetPrivilege(SE_RESTORE_NAME);
// Not sure if we really need it, but let's request anyway.
SetPrivilege(SE_CREATE_SYMBOLIC_LINK_NAME);
PrivSet=true;
}
const DWORD BufSize=sizeof(REPARSE_DATA_BUFFER)+2*NM+1024;
Array<byte> Buf(BufSize);
REPARSE_DATA_BUFFER *rdb=(REPARSE_DATA_BUFFER *)&Buf[0];
wchar SubstName[NM];
wcsncpyz(SubstName,hd->RedirName,ASIZE(SubstName));
size_t SubstLength=wcslen(SubstName);
wchar PrintName[NM],*PrintNameSrc=SubstName,*PrintNameDst=PrintName;
bool WinPrefix=wcsncmp(PrintNameSrc,L"\\??\\",4)==0;
if (WinPrefix)
PrintNameSrc+=4;
if (WinPrefix && wcsncmp(PrintNameSrc,L"UNC\\",4)==0)
{
*(PrintNameDst++)='\\'; // Insert second \ in beginning of share name.
PrintNameSrc+=3;
}
wcscpy(PrintNameDst,PrintNameSrc);
size_t PrintLength=wcslen(PrintName);
bool AbsPath=WinPrefix;
// IsFullPath is not really needed here, AbsPath check is enough.
// We added it just for extra safety, in case some Windows version would
// allow to create absolute targets with SYMLINK_FLAG_RELATIVE.
// Use hd->FileName instead of Name, since Name can include the destination
// path as a prefix, which can confuse IsRelativeSymlinkSafe algorithm.
if (!Cmd->AbsoluteLinks && (AbsPath || IsFullPath(hd->RedirName) ||
!IsRelativeSymlinkSafe(Cmd,hd->FileName,Name,hd->RedirName)))
return false;
CreatePath(Name,true);
// 'DirTarget' check is important for Unix symlinks to directories.
// Unix symlinks do not have their own 'directory' attribute.
if (hd->Dir || hd->DirTarget)
{
if (!CreateDirectory(Name,NULL))
return false;
}
else
{
HANDLE hFile=CreateFile(Name,GENERIC_WRITE,0,NULL,CREATE_NEW,FILE_ATTRIBUTE_NORMAL,NULL);
if (hFile == INVALID_HANDLE_VALUE)
return false;
CloseHandle(hFile);
}
if (hd->RedirType==FSREDIR_JUNCTION)
{
rdb->ReparseTag=IO_REPARSE_TAG_MOUNT_POINT;
rdb->ReparseDataLength=USHORT(
sizeof(rdb->MountPointReparseBuffer.SubstituteNameOffset)+
sizeof(rdb->MountPointReparseBuffer.SubstituteNameLength)+
sizeof(rdb->MountPointReparseBuffer.PrintNameOffset)+
sizeof(rdb->MountPointReparseBuffer.PrintNameLength)+
(SubstLength+1)*sizeof(WCHAR)+(PrintLength+1)*sizeof(WCHAR));
rdb->Reserved=0;
rdb->MountPointReparseBuffer.SubstituteNameOffset=0;
rdb->MountPointReparseBuffer.SubstituteNameLength=USHORT(SubstLength*sizeof(WCHAR));
wcscpy(rdb->MountPointReparseBuffer.PathBuffer,SubstName);
rdb->MountPointReparseBuffer.PrintNameOffset=USHORT((SubstLength+1)*sizeof(WCHAR));
rdb->MountPointReparseBuffer.PrintNameLength=USHORT(PrintLength*sizeof(WCHAR));
wcscpy(rdb->MountPointReparseBuffer.PathBuffer+SubstLength+1,PrintName);
}
else
if (hd->RedirType==FSREDIR_WINSYMLINK || hd->RedirType==FSREDIR_UNIXSYMLINK)
{
rdb->ReparseTag=IO_REPARSE_TAG_SYMLINK;
rdb->ReparseDataLength=USHORT(
sizeof(rdb->SymbolicLinkReparseBuffer.SubstituteNameOffset)+
sizeof(rdb->SymbolicLinkReparseBuffer.SubstituteNameLength)+
sizeof(rdb->SymbolicLinkReparseBuffer.PrintNameOffset)+
sizeof(rdb->SymbolicLinkReparseBuffer.PrintNameLength)+
sizeof(rdb->SymbolicLinkReparseBuffer.Flags)+
(SubstLength+1)*sizeof(WCHAR)+(PrintLength+1)*sizeof(WCHAR));
rdb->Reserved=0;
rdb->SymbolicLinkReparseBuffer.SubstituteNameOffset=0;
rdb->SymbolicLinkReparseBuffer.SubstituteNameLength=USHORT(SubstLength*sizeof(WCHAR));
wcscpy(rdb->SymbolicLinkReparseBuffer.PathBuffer,SubstName);
rdb->SymbolicLinkReparseBuffer.PrintNameOffset=USHORT((SubstLength+1)*sizeof(WCHAR));
rdb->SymbolicLinkReparseBuffer.PrintNameLength=USHORT(PrintLength*sizeof(WCHAR));
wcscpy(rdb->SymbolicLinkReparseBuffer.PathBuffer+SubstLength+1,PrintName);
rdb->SymbolicLinkReparseBuffer.Flags=AbsPath ? 0:SYMLINK_FLAG_RELATIVE;
}
else
return false;
HANDLE hFile=CreateFile(Name,GENERIC_READ|GENERIC_WRITE,0,NULL,
OPEN_EXISTING,FILE_FLAG_OPEN_REPARSE_POINT|
FILE_FLAG_BACKUP_SEMANTICS,NULL);
if (hFile==INVALID_HANDLE_VALUE)
return false;
DWORD Returned;
if (!DeviceIoControl(hFile,FSCTL_SET_REPARSE_POINT,rdb,
FIELD_OFFSET(REPARSE_DATA_BUFFER,GenericReparseBuffer)+
rdb->ReparseDataLength,NULL,0,&Returned,NULL))
{
CloseHandle(hFile);
uiMsg(UIERROR_SLINKCREATE,UINULL,Name);
DWORD LastError=GetLastError();
if ((LastError==ERROR_ACCESS_DENIED || LastError==ERROR_PRIVILEGE_NOT_HELD) &&
!IsUserAdmin())
uiMsg(UIERROR_NEEDADMIN);
ErrHandler.SysErrMsg();
ErrHandler.SetErrorCode(RARX_CREATE);
if (hd->Dir)
RemoveDirectory(Name);
else
DeleteFile(Name);
return false;
}
File LinkFile;
LinkFile.SetHandle(hFile);
LinkFile.SetOpenFileTime(
Cmd->xmtime==EXTTIME_NONE ? NULL:&hd->mtime,
Cmd->xctime==EXTTIME_NONE ? NULL:&hd->ctime,
Cmd->xatime==EXTTIME_NONE ? NULL:&hd->atime);
LinkFile.Close();
if (!Cmd->IgnoreGeneralAttr)
SetFileAttr(Name,hd->FileAttr);
return true;
}