name.c File Reference

#include <ntoskrnl.h>
#include <debug.h>

Include dependency graph for name.c:

Go to the source code of this file.

Macros
#define	NDEBUG

Functions
BOOLEAN NTAPI	FsRtlIsNameInExpressionPrivate (IN PUNICODE_STRING Expression, IN PUNICODE_STRING Name, IN BOOLEAN IgnoreCase, IN PWCHAR UpcaseTable OPTIONAL)
BOOLEAN NTAPI	FsRtlAreNamesEqual (IN PCUNICODE_STRING Name1, IN PCUNICODE_STRING Name2, IN BOOLEAN IgnoreCase, IN PCWCH UpcaseTable OPTIONAL)
VOID NTAPI	FsRtlDissectName (IN UNICODE_STRING Name, OUT PUNICODE_STRING FirstPart, OUT PUNICODE_STRING RemainingPart)
BOOLEAN NTAPI	FsRtlDoesNameContainWildCards (IN PUNICODE_STRING Name)
BOOLEAN NTAPI	FsRtlIsNameInExpression (IN PUNICODE_STRING Expression, IN PUNICODE_STRING Name, IN BOOLEAN IgnoreCase, IN PWCHAR UpcaseTable OPTIONAL)

Macro Definition Documentation

NDEBUG

#define NDEBUG

Definition at line 15 of file name.c.

Function Documentation

FsRtlAreNamesEqual()

BOOLEAN NTAPI FsRtlAreNamesEqual	(	IN PCUNICODE_STRING	Name1,
		IN PCUNICODE_STRING	Name2,
		IN BOOLEAN	IgnoreCase,
		IN PCWCH UpcaseTable	OPTIONAL
	)

Definition at line 296 of file name.c.

{
    UNICODE_STRING UpcaseName1;
    UNICODE_STRING UpcaseName2;
    BOOLEAN StringsAreEqual, MemoryAllocated = FALSE;
    USHORT i;
    NTSTATUS Status;
    PAGED_CODE();

    /* Well, first check their size */
    if (Name1->Length != Name2->Length) return FALSE;

    /* Check if the caller didn't give an upcase table */
    if ((IgnoreCase) && !(UpcaseTable))
    {
        /* Upcase the string ourselves */
        Status = RtlUpcaseUnicodeString(&UpcaseName1, Name1, TRUE);
        if (!NT_SUCCESS(Status)) RtlRaiseStatus(Status);

        /* Upcase the second string too */
        Status = RtlUpcaseUnicodeString(&UpcaseName2, Name2, TRUE);
        if (!NT_SUCCESS(Status))
        {
            RtlFreeUnicodeString(&UpcaseName1);
            RtlRaiseStatus(Status);
        }

        Name1 = &UpcaseName1;
        Name2 = &UpcaseName2;

        /* Make sure we go through the path below, but free the strings */
        IgnoreCase = FALSE;
        MemoryAllocated = TRUE;
    }

    /* Do a case-sensitive search */
    if (!IgnoreCase)
    {
        /* Use a raw memory compare */
        StringsAreEqual = RtlEqualMemory(Name1->Buffer,
                                         Name2->Buffer,
                                         Name1->Length);

        /* Check if we allocated strings */
        if (MemoryAllocated)
        {
            /* Free them */
            RtlFreeUnicodeString(&UpcaseName1);
            RtlFreeUnicodeString(&UpcaseName2);
        }

        /* Return the equality */
        return StringsAreEqual;
    }
    else
    {
        /* Case in-sensitive search */
        for (i = 0; i < Name1->Length / sizeof(WCHAR); i++)
        {
            /* Check if the character matches */
            if (UpcaseTable[Name1->Buffer[i]] != UpcaseTable[Name2->Buffer[i]])
            {
                /* Non-match found! */
                return FALSE;
            }
        }

        /* We finished the loop so we are equal */
        return TRUE;
    }
}

Referenced by Ext2SetLinkInfo(), Ext2SetRenameInfo(), FatSetRenameInfo(), FFSSetRenameInfo(), file_create(), FindFile(), lie_about_fs_type(), registry_load_volume_options(), registry_mark_volume_unmounted_path(), RfsdSetRenameInfo(), and VfatSetRenameInformation().

FsRtlDissectName()

VOID NTAPI FsRtlDissectName	(	IN UNICODE_STRING	Name,
		OUT PUNICODE_STRING	FirstPart,
		OUT PUNICODE_STRING	RemainingPart
	)

Definition at line 398 of file name.c.

{
    USHORT FirstPosition, i;
    USHORT SkipFirstSlash = 0;
    PAGED_CODE();

    /* Zero the strings before continuing */
    RtlZeroMemory(FirstPart, sizeof(UNICODE_STRING));
    RtlZeroMemory(RemainingPart, sizeof(UNICODE_STRING));

    /* Just quit if the string is empty */
    if (!Name.Length) return;

    /* Find first backslash */
    FirstPosition = Name.Length / sizeof(WCHAR) ;
    for (i = 0; i < Name.Length / sizeof(WCHAR); i++)
    {
        /* If we found one... */
        if (Name.Buffer[i] == L'\\')
        {
            /* If it begins string, just notice it and continue */
            if (i == 0)
            {
                SkipFirstSlash = 1;
            }
            else
            {
                /* Else, save its position and break out of the loop */
                FirstPosition = i;
                break;
            }
        }
    }

    /* Set up the first result string */
    FirstPart->Buffer = Name.Buffer + SkipFirstSlash;
    FirstPart->Length = (FirstPosition - SkipFirstSlash) * sizeof(WCHAR);
    FirstPart->MaximumLength = FirstPart->Length;

    /* And second one, if necessary */
    if (FirstPosition < (Name.Length / sizeof(WCHAR)))
    {
        RemainingPart->Buffer = Name.Buffer + FirstPosition + 1;
        RemainingPart->Length = Name.Length - (FirstPosition + 1) * sizeof(WCHAR);
        RemainingPart->MaximumLength = RemainingPart->Length;
    }
}

Referenced by AddFileName(), Ext2CreateFile(), FFSCreateFile(), NtfsLookupFileAt(), RfsdCreateFile(), and START_TEST().

FsRtlDoesNameContainWildCards()

BOOLEAN NTAPI FsRtlDoesNameContainWildCards

(

IN PUNICODE_STRING

Name

)

Definition at line 464 of file name.c.

{
    PWCHAR Ptr;
    PAGED_CODE();

    /* Loop through every character */
    if (Name->Length)
    {
        Ptr = Name->Buffer + (Name->Length / sizeof(WCHAR)) - 1;
        while ((Ptr >= Name->Buffer) && (*Ptr != L'\\'))
        {
            /* Check for Wildcard */
            if (FsRtlIsUnicodeCharacterWild(*Ptr)) return TRUE;
            Ptr--;
        }
    }

    /* Nothing Found */
    return FALSE;
}

Referenced by CdInitializeEnumeration(), Ext2CreateFile(), Ext2FillEntry(), Ext2QueryDirectory(), Ext2SetLinkInfo(), Ext2SetRenameInfo(), FFSCreateFile(), FFSQueryDirectory(), FFSSetRenameInfo(), FindFile(), FsRtlIsNameInExpressionPrivate(), query_directory(), RfsdCreateFile(), RfsdDirectoryCallback(), RfsdSetRenameInfo(), RxCanonicalizeNameAndObtainNetRoot(), RxQueryDirectory(), and UDFQueryDirectory().

FsRtlIsNameInExpression()

BOOLEAN NTAPI FsRtlIsNameInExpression	(	IN PUNICODE_STRING	Expression,
		IN PUNICODE_STRING	Name,
		IN BOOLEAN	IgnoreCase,
		IN PWCHAR UpcaseTable	OPTIONAL
	)

Definition at line 514 of file name.c.

{
    BOOLEAN Result;
    NTSTATUS Status;
    UNICODE_STRING IntName;

    if (IgnoreCase && !UpcaseTable)
    {
        Status = RtlUpcaseUnicodeString(&IntName, Name, TRUE);
        if (!NT_SUCCESS(Status))
        {
            ExRaiseStatus(Status);
        }
        Name = &IntName;
        IgnoreCase = FALSE;
    }
    else
    {
        IntName.Buffer = NULL;
    }

    Result = FsRtlIsNameInExpressionPrivate(Expression, Name, IgnoreCase, UpcaseTable);

    if (IntName.Buffer != NULL)
    {
        RtlFreeUnicodeString(&IntName);
    }

    return Result;
}

Referenced by CdIsNameInExpression(), CompareFileName(), Ext2FillEntry(), Ext2QueryDirectory(), FFSQueryDirectory(), FindFile(), FsRtlIsNameInExpressionTest(), query_directory(), RfsdDirectoryCallback(), UDFIsNameInExpression(), vfatAttachFCBToFileObject(), vfatDestroyFCB(), vfatFCBInitializeCacheFromVolume(), vfatGrabFCB(), and vfatReleaseFCB().

FsRtlIsNameInExpressionPrivate()

BOOLEAN NTAPI FsRtlIsNameInExpressionPrivate	(	IN PUNICODE_STRING	Expression,
		IN PUNICODE_STRING	Name,
		IN BOOLEAN	IgnoreCase,
		IN PWCHAR UpcaseTable	OPTIONAL
	)

Definition at line 21 of file name.c.

{
    USHORT Offset, Position, BackTrackingPosition, OldBackTrackingPosition;
    USHORT BackTrackingBuffer[16], OldBackTrackingBuffer[16] = {0};
    PUSHORT BackTrackingSwap, BackTracking = BackTrackingBuffer, OldBackTracking = OldBackTrackingBuffer;
    ULONG BackTrackingBufferSize = RTL_NUMBER_OF(BackTrackingBuffer);
    PVOID AllocatedBuffer = NULL;
    UNICODE_STRING IntExpression;
    USHORT ExpressionPosition, NamePosition = 0, MatchingChars = 1;
    BOOLEAN EndOfName = FALSE;
    BOOLEAN Result;
    BOOLEAN DontSkipDot;
    WCHAR CompareChar;
    PAGED_CODE();

    /* Check if we were given strings at all */
    if (!Name->Length || !Expression->Length)
    {
        /* Return TRUE if both strings are empty, otherwise FALSE */
        if (!Name->Length && !Expression->Length)
            return TRUE;
        else
            return FALSE;
    }

    /* Check for a shortcut: just one wildcard */
    if (Expression->Length == sizeof(WCHAR))
    {
        if (Expression->Buffer[0] == L'*')
            return TRUE;
    }

    ASSERT(!IgnoreCase || UpcaseTable);

    /* Another shortcut, wildcard followed by some string */
    if (Expression->Buffer[0] == L'*')
    {
        /* Copy Expression to our local variable */
        IntExpression = *Expression;

        /* Skip the first char */
        IntExpression.Buffer++;
        IntExpression.Length -= sizeof(WCHAR);

        /* Continue only if the rest of the expression does NOT contain
           any more wildcards */
        if (!FsRtlDoesNameContainWildCards(&IntExpression))
        {
            /* Check for a degenerate case */
            if (Name->Length < (Expression->Length - sizeof(WCHAR)))
                return FALSE;

            /* Calculate position */
            NamePosition = (Name->Length - IntExpression.Length) / sizeof(WCHAR);

            /* Compare */
            if (!IgnoreCase)
            {
                /* We can just do a byte compare */
                return RtlEqualMemory(IntExpression.Buffer,
                                      Name->Buffer + NamePosition,
                                      IntExpression.Length);
            }
            else
            {
                /* Not so easy, need to upcase and check char by char */
                for (ExpressionPosition = 0; ExpressionPosition < (IntExpression.Length / sizeof(WCHAR)); ExpressionPosition++)
                {
                    /* Assert that expression is already upcased! */
                    ASSERT(IntExpression.Buffer[ExpressionPosition] == UpcaseTable[IntExpression.Buffer[ExpressionPosition]]);

                    /* Now compare upcased name char with expression */
                    if (UpcaseTable[Name->Buffer[NamePosition + ExpressionPosition]] !=
                        IntExpression.Buffer[ExpressionPosition])
                    {
                        return FALSE;
                    }
                }

                /* It matches */
                return TRUE;
            }
        }
    }

    /* Name parsing loop */
    for (; !EndOfName; MatchingChars = BackTrackingPosition, NamePosition++)
    {
        /* Reset positions */
        OldBackTrackingPosition = BackTrackingPosition = 0;

        if (NamePosition >= Name->Length / sizeof(WCHAR))
        {
            EndOfName = TRUE;
            if (MatchingChars && (OldBackTracking[MatchingChars - 1] == Expression->Length * 2))
                break;
        }

        while (MatchingChars > OldBackTrackingPosition)
        {
            ExpressionPosition = (OldBackTracking[OldBackTrackingPosition++] + 1) / 2;

            /* Expression parsing loop */
            for (Offset = 0; ExpressionPosition < Expression->Length; Offset = sizeof(WCHAR))
            {
                ExpressionPosition += Offset;

                if (ExpressionPosition == Expression->Length)
                {
                    BackTracking[BackTrackingPosition++] = Expression->Length * 2;
                    break;
                }

                /* If buffer too small */
                if (BackTrackingPosition > BackTrackingBufferSize - 3)
                {
                    /* We should only ever get here once! */
                    ASSERT(AllocatedBuffer == NULL);
                    ASSERT((BackTracking == BackTrackingBuffer) || (BackTracking == OldBackTrackingBuffer));
                    ASSERT((OldBackTracking == BackTrackingBuffer) || (OldBackTracking == OldBackTrackingBuffer));

                    /* Calculate buffer size */
                    BackTrackingBufferSize = Expression->Length / sizeof(WCHAR) * 2 + 1;

                    /* Allocate memory for both back-tracking buffers */
                    AllocatedBuffer = ExAllocatePoolWithTag(PagedPool | POOL_RAISE_IF_ALLOCATION_FAILURE,
                                                            2 * BackTrackingBufferSize * sizeof(USHORT),
                                                            'nrSF');
                    if (AllocatedBuffer == NULL)
                    {
                        DPRINT1("Failed to allocate BackTracking buffer. BackTrackingBufferSize = =x%lx\n",
                                BackTrackingBufferSize);
                        Result = FALSE;
                        goto Exit;
                    }

                    /* Copy BackTracking content. Note that it can point to either BackTrackingBuffer or OldBackTrackingBuffer */
                    RtlCopyMemory(AllocatedBuffer,
                                  BackTracking,
                                  RTL_NUMBER_OF(BackTrackingBuffer) * sizeof(USHORT));

                    /* Place current Backtracking is at the start of the new buffer */
                    BackTracking = AllocatedBuffer;

                    /* Copy OldBackTracking content */
                    RtlCopyMemory(&BackTracking[BackTrackingBufferSize],
                                  OldBackTracking,
                                  RTL_NUMBER_OF(OldBackTrackingBuffer) * sizeof(USHORT));

                    /* Place current OldBackTracking after current BackTracking in the buffer */
                    OldBackTracking = &BackTracking[BackTrackingBufferSize];
                }

                /* Basic check to test if chars are equal */
                CompareChar = (NamePosition >= Name->Length / sizeof(WCHAR)) ? UNICODE_NULL : (IgnoreCase ? UpcaseTable[Name->Buffer[NamePosition]] :
                                           Name->Buffer[NamePosition]);
                if (Expression->Buffer[ExpressionPosition / sizeof(WCHAR)] == CompareChar && !EndOfName)
                {
                    BackTracking[BackTrackingPosition++] = (ExpressionPosition + sizeof(WCHAR)) * 2;
                }
                /* Check cases that eat one char */
                else if (Expression->Buffer[ExpressionPosition / sizeof(WCHAR)] == L'?' && !EndOfName)
                {
                    BackTracking[BackTrackingPosition++] = (ExpressionPosition + sizeof(WCHAR)) * 2;
                }
                /* Test star */
                else if (Expression->Buffer[ExpressionPosition / sizeof(WCHAR)] == L'*')
                {
                    BackTracking[BackTrackingPosition++] = ExpressionPosition * 2;
                    BackTracking[BackTrackingPosition++] = (ExpressionPosition * 2) + 3;
                    continue;
                }
                /* Check DOS_STAR */
                else if (Expression->Buffer[ExpressionPosition / sizeof(WCHAR)] == DOS_STAR)
                {
                    /* Look for last dot */
                    DontSkipDot = TRUE;
                    if (!EndOfName && Name->Buffer[NamePosition] == '.')
                    {
                        for (Position = NamePosition + 1; Position < Name->Length / sizeof(WCHAR); Position++)
                        {
                            if (Name->Buffer[Position] == L'.')
                            {
                                DontSkipDot = FALSE;
                                break;
                            }
                        }
                    }

                    if (EndOfName || Name->Buffer[NamePosition] != L'.' || !DontSkipDot)
                        BackTracking[BackTrackingPosition++] = ExpressionPosition * 2;

                    BackTracking[BackTrackingPosition++] = (ExpressionPosition * 2) + 3;
                    continue;
                }
                /* Check DOS_DOT */
                else if (Expression->Buffer[ExpressionPosition / sizeof(WCHAR)] == DOS_DOT)
                {
                    if (EndOfName) continue;

                    if (Name->Buffer[NamePosition] == L'.')
                        BackTracking[BackTrackingPosition++] = (ExpressionPosition + sizeof(WCHAR)) * 2;
                }
                /* Check DOS_QM */
                else if (Expression->Buffer[ExpressionPosition / sizeof(WCHAR)] == DOS_QM)
                {
                    if (EndOfName || Name->Buffer[NamePosition] == L'.') continue;

                    BackTracking[BackTrackingPosition++] = (ExpressionPosition + sizeof(WCHAR)) * 2;
                }

                /* Leave from loop */
                break;
            }

            for (Position = 0; MatchingChars > OldBackTrackingPosition && Position < BackTrackingPosition; Position++)
            {
                while (MatchingChars > OldBackTrackingPosition &&
                       BackTracking[Position] > OldBackTracking[OldBackTrackingPosition])
                {
                    ++OldBackTrackingPosition;
                }
            }
        }

        /* Swap pointers */
        BackTrackingSwap = BackTracking;
        BackTracking = OldBackTracking;
        OldBackTracking = BackTrackingSwap;
    }

    /* Store result value */
    Result = MatchingChars > 0 && (OldBackTracking[MatchingChars - 1] == (Expression->Length * 2));

Exit:

    /* Frees the memory if necessary */
    if (AllocatedBuffer != NULL)
    {
        ExFreePoolWithTag(AllocatedBuffer, 'nrSF');
    }

    return Result;
}

Referenced by FsRtlIsNameInExpression().