https://git.reactos.org/?p=reactos.git;a=commitdiff;h=e12abf63c53670009f6843fa705ab7d392b66cf9
commit e12abf63c53670009f6843fa705ab7d392b66cf9
Author: Pierre Schweitzer <pie...@reactos.org>
AuthorDate: Mon Aug 19 10:44:56 2019 +0200
Commit: Pierre Schweitzer <pie...@reactos.org>
CommitDate: Mon Aug 19 10:45:50 2019 +0200
[NTOSKRNL] Handle symlink parsing when it's bound to a specific object
---
ntoskrnl/ob/oblink.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 93 insertions(+), 1 deletion(-)
diff --git a/ntoskrnl/ob/oblink.c b/ntoskrnl/ob/oblink.c
index 712143e1ed7..67cb36385dd 100644
--- a/ntoskrnl/ob/oblink.c
+++ b/ntoskrnl/ob/oblink.c
@@ -5,6 +5,7 @@
* PURPOSE: Implements symbolic links
* PROGRAMMERS: Alex Ionescu (a...@relsoft.net)
* David Welch (we...@mcmail.com)
+* Pierre Schweitzer
*/
/* INCLUDES *****************************************************************/
@@ -481,7 +482,98 @@ ObpParseSymbolicLink(IN PVOID ParsedObject,
/* Check if this symlink is bound to a specific object */
if (SymlinkObject->LinkTargetObject)
{
- UNIMPLEMENTED;
+ /* No name to reparse, directly reparse the object */
+ if (!SymlinkObject->LinkTargetRemaining.Length)
+ {
+ *NextObject = SymlinkObject->LinkTargetObject;
+ return STATUS_REPARSE_OBJECT;
+ }
+
+ TempLength = SymlinkObject->LinkTargetRemaining.Length;
+ /* The target and remaining names aren't empty, so check for slashes */
+ if (SymlinkObject->LinkTargetRemaining.Buffer[TempLength /
sizeof(WCHAR) - 1] == OBJ_NAME_PATH_SEPARATOR &&
+ RemainingName->Buffer[0] == OBJ_NAME_PATH_SEPARATOR)
+ {
+ /* Reduce the length by one to cut off the extra '\' */
+ TempLength -= sizeof(OBJ_NAME_PATH_SEPARATOR);
+ }
+
+ /* Calculate the new length */
+ LengthUsed = TempLength + RemainingName->Length;
+ LengthUsed += (sizeof(WCHAR) * (RemainingName->Buffer -
FullPath->Buffer));
+
+ /* Check if it's not too much */
+ if (LengthUsed > 0xFFF0)
+ return STATUS_NAME_TOO_LONG;
+
+ /* If FullPath is enough, use it */
+ if (FullPath->MaximumLength > LengthUsed)
+ {
+ /* Update remaining length if appropriate */
+ if (RemainingName->Length)
+ {
+ RtlMoveMemory((PVOID)((ULONG_PTR)RemainingName->Buffer +
TempLength),
+ RemainingName->Buffer,
+ RemainingName->Length);
+ }
+
+ /* And move the target object name */
+ RtlCopyMemory(RemainingName->Buffer,
+ SymlinkObject->LinkTargetRemaining.Buffer,
+ TempLength);
+
+ /* Finally update the full path with what we parsed */
+ FullPath->Length += SymlinkObject->LinkTargetRemaining.Length;
+ RemainingName->Length += SymlinkObject->LinkTargetRemaining.Length;
+ RemainingName->MaximumLength += RemainingName->Length +
sizeof(WCHAR);
+ FullPath->Buffer[FullPath->Length / sizeof(WCHAR)] = UNICODE_NULL;
+
+ /* And reparse */
+ *NextObject = SymlinkObject->LinkTargetObject;
+ return STATUS_REPARSE_OBJECT;
+ }
+
+ /* FullPath is not enough, we'll have to reallocate */
+ MaximumLength = LengthUsed + sizeof(WCHAR);
+ NewTargetPath = ExAllocatePoolWithTag(NonPagedPool,
+ MaximumLength,
+ OB_NAME_TAG);
+ if (!NewTargetPath) return STATUS_INSUFFICIENT_RESOURCES;
+
+ /* Copy path begin */
+ RtlCopyMemory(NewTargetPath,
+ FullPath->Buffer,
+ sizeof(WCHAR) * (RemainingName->Buffer -
FullPath->Buffer));
+
+ /* Copy path end (if any) */
+ if (RemainingName->Length)
+ {
+
RtlCopyMemory((PVOID)((ULONG_PTR)&NewTargetPath[RemainingName->Buffer -
FullPath->Buffer] + TempLength),
+ RemainingName->Buffer,
+ RemainingName->Length);
+ }
+
+ /* And finish path with bound object */
+ RtlCopyMemory(&NewTargetPath[RemainingName->Buffer - FullPath->Buffer],
+ SymlinkObject->LinkTargetRemaining.Buffer,
+ TempLength);
+
+ /* Free old buffer */
+ ExFreePool(FullPath->Buffer);
+
+ /* Set new buffer in FullPath */
+ FullPath->Buffer = NewTargetPath;
+ FullPath->MaximumLength = MaximumLength;
+ FullPath->Length = LengthUsed;
+
+ /* Update remaining with what we handled */
+ RemainingName->Length = LengthUsed + (ULONG_PTR)NewTargetPath -
(ULONG_PTR)&NewTargetPath[RemainingName->Buffer - FullPath->Buffer];
+ RemainingName->Buffer = &NewTargetPath[RemainingName->Buffer -
FullPath->Buffer];
+ RemainingName->MaximumLength = RemainingName->Length + sizeof(WCHAR);
+
+ /* Reparse! */
+ *NextObject = SymlinkObject->LinkTargetObject;
+ return STATUS_REPARSE_OBJECT;
}
/* Set the target path and length */
